1 Kernel Release Notes

This document describes the changes made to the Kernel application.

1.1  Kernel 8.0

Fixed Bugs and Malfunctions

• A bug has been fixed for the internal inet_res resolver cache that handled a resolver configuration file status timer incorrectly and caused performance problems due to many unnecessary file system accesses.

  Own Id: OTP-14700 Aux Id: PR-2848

• Change the value of the tag head returned by disk_log:info/1 from {ok, Head} to just Head.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-16809 Aux Id: ERL-1313

• Two options have been added to erl_call. The -fetch_stdout option fetches stdout data resulting from the code invoked by erl_call. The -fetch_stdout option disables printing of the result term. In order to implement the first of these two options a new function called ei_xrpc_from has been added to erl_interface. For details see the erl_call documentation and erl_interface documentation.

  Own Id: OTP-17132

• Missing runtime dependencies has been added to this application.

  Own Id: OTP-17243 Aux Id: PR-4557

• inet:get_rc/0 has been corrected to return host entries as separate entries instead of (incorrectly) in a list within the list. This bug was introduced by OTP-16487 in OTP-23.0-rc1.

  Own Id: OTP-17262 Aux Id: GH-4588, PR-4604, OTP-16487

• The type gen_tcp:option_name() had a duplicate pktoptions value.

  Own Id: OTP-17277

• Fixed removal of empty groups from internal state in pg.

  Own Id: OTP-17286 Aux Id: PR-4619

• erl -remsh now prints an error message when it fails to connect to the remote node.

  Own Id: OTP-17287 Aux Id: PR-4581

• Fix bugs related to corrupt shell history files.

  Error messages printed by shell history are now logged as logger error reports instead of written to standard error.

  Own Id: OTP-17288 Aux Id: PR-4581

• A logger warning is now issues when too many arguments are given to -name or -sname. Example: erl -name a b.

  Own Id: OTP-17315 Aux Id: GH-4626

Improvements and New Features

• The cache used by the DNS resolver inet_res has been improved to use ETS lookups instead of server calls. This is a considerable speed improvement for cache hits.

  Own Id: OTP-13126 Aux Id: PR-3041

• The cache ETS table type for the internal DNS resolver inet_res has changed type (internally) to get better speed and atomicity.

  Own Id: OTP-14485 Aux Id: PR-2891

• The experimental socket module can now use any protocol (by name) the OS supports. Suggested in PR-2641, implemented in PR-2670.

  Own Id: OTP-14601 Aux Id: PR-2641, PR-2670, OTP-16749

• The DNS resolver inet_res has been updated to support CAA (RFC 6844) and URI (RFC 7553) records.

  Own Id: OTP-16517 Aux Id: PR-2827

• A compatibility adaptor for gen_tcp to use the new socket API has been implemented (gen_tcp_socket). Used when setting the kernel application variable inet_backend = socket.

  Own Id: OTP-16611 Aux Id: OTP-16749

• Extended error information for failing BIF calls as proposed in EEP 54 has been implemented.

  When a BIF call from the Erlang shell fails, more information about which argument or arguments that were in error will be printed. The same extended error information will by proc_lib, common_test, and qlc when BIF calls fail.

  For applications that wish to provide the same extended error information, there are new functions erl_error:format_exception/3 and erl_error:format_exception/4.

  There is a new error/3 BIF that allows applications or libraries to provide extended error information in the same way for their own exceptions.

  Own Id: OTP-16686

• The file server can now be bypassed in file:delete/1,2 with the raw option.

  Own Id: OTP-16698 Aux Id: PR-2634

• An example implementation of Erlang distribution over UDS using distribution processes has been introduced.

  Thanks to Jérôme de Bretagne

  Own Id: OTP-16703 Aux Id: PR-2620

• Process aliases as outlined by EEP 53 has been introduced. Process aliases is introduced in order to provide a lightweight mechanism that can prevent late replies after timeout or connection loss. For more information, see EEP 53 and the documentation of the new alias/1 BIF and the new options to the monitor/3 BIF.

  The call operation in the framework used by gen_server, gen_statem, and gen_event has been updated to utilize alias in order to prevent late responses. The gen_statem behavior still use a proxy process in the distributed case, since it has always prevented late replies and aliases wont work against pre OTP 24 nodes. The proxy process can be removed in OTP 26.

  The alias feature also made it possible to introduce new functions similar to the erpc:receive_response() function in the gen behaviors, so the new functions gen_server:receive_response(), gen_statem:receive_response(), gen_event:receive_response() have also been introduced.

  Own Id: OTP-16718 Aux Id: PR-2735

• The experimental new socket API has been further developed. Some backwards incompatible changes with respect to OTP 23 have been made.

  The control message format has been changed so a decoded value is now in the 'value' field instead of in the 'data' field. The 'data' field now always contains binary data.

  Some type names have been changed regarding message headers and control message headers.

  socket:bind/2 now returns plain ok instead of {ok, Port} which was only relevant for the inet and inet6 address families and often not interesting. To find out which port was chosen use socket:sockname/1.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-16749 Aux Id: OTP-14601

• New function os:env/0 returns all OS environment variables as a list of 2-tuples.

  Own Id: OTP-16793 Aux Id: ERL-1332, PR-2740

• Remove the support for distributed disk logs. The new function disk_log:all/0 is to be used instead of disk_log:accessible_logs/0. The function disk_log:close/1 is to be used instead of disk_log:lclose/1,2.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-16811

• Expand the spec for erl_epmd:listen_port_please/2 to mirror erl_epmd:port_please/2.

  Own Id: OTP-16947 Aux Id: PR-2781

• A new erl parameter for specifying a file descriptor with configuration data has been added. This makes it possible to pass the parameter "-configfd FD" when executing the erl command. When this option is given, the system will try to read and parse configuration parameters from the file descriptor.

  Own Id: OTP-16952

• The experimental HiPE application has been removed, together with all related functionality in other applications.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-16963

• The pg2 module has been removed.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-16968

• Accept references up to a size of 160-bits from remote nodes. This is the first step in an upgrade path toward using references up to 160-bits in a future OTP release.

  Own Id: OTP-17005 Aux Id: OTP-16718

• Allow utf-8 binaries as parts of logger_formatter template.

  Own Id: OTP-17015

• Let disk_log:open/1 change the size if a wrap log is opened for the first time, that is, the disk log process does not exist, and the value of option size does not match the current size of the disk log.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-17062 Aux Id: ERL-1418, GH-4469, ERIERL-537

• Allow the shell history of an erlang node to be fetched and stores using a custom callback module. See shell_history configuration parameter in the kernel documentation for more details.

  Own Id: OTP-17103 Aux Id: PR-2949

• The simple logger (used to log events that happen before kernel has been started) has been improved to print prettier error messages.

  Own Id: OTP-17106 Aux Id: PR-2885

• Fix various issues with the gen_tcp_socket. Including documenting some incompatibilities.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-17156

• Added support in logger for setting primary metadata. The primary metadata is passed as a base metadata to all log events in the system. See Metadata in the Logger chapter of the Kernel User's Guide for more details.

  Own Id: OTP-17181 Aux Id: PR-2457

• Recognize new key 'optional_applications' in application resource files.

  Own Id: OTP-17189 Aux Id: PR-2675

• The Fun's passed to logger:log/2,3,4 can now return metadata that will only be fetched when needed. See logger:log/2,3,4 for more details.

  Own Id: OTP-17198 Aux Id: PR-2721

• erpc:multicall() has been rewritten to be able to utilize the newly introduced and improved reference/receive optimization.

  Own Id: OTP-17201 Aux Id: PR-4534

• Add utility fiunction inet:info/1 to provide miscellaneous info about a socket.

  Own Id: OTP-17203 Aux Id: OTP-17156

• The behaviour for gen_tcp:connect/3,4 has been changed to not per default bind to an address, which allows the network stack to delay the address and port selection to when the remote address is known. This allows better port re-use, and thus enables far more outgoing connections, since the ephemeral port range no longer has to be a hard limit.

  There is a theoretical possibility that this behaviour change can affect the set of possible error values, or have other small implications on some platforms.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-17216 Aux Id: PR-2989

• An option {nxdomain_reply, boolean()} has been implemented in the DNS resolver inet_res. It is useful since an nxdomain error from a name server does contain the SOA record if the domain exists at all. This record is useful to determine a TTL for negative caching of the failed entry.

  Own Id: OTP-17266 Aux Id: PR-4564

• Optimized lookup of local processes part of groups in pg.

  Own Id: OTP-17284 Aux Id: PR-4615

1.2  Kernel 7.3

Fixed Bugs and Malfunctions

• The range check for compression pointers in DNS encoding was faulty, which caused incorrect label compression encoding for very large DNS messages; larger than about 16 kBytes, such as AXFR responses. This more than 11 year old bug has now been corrected.

  Own Id: OTP-13641 Aux Id: PR-2959

• Fix of internal links in the erpc documentation.

  Own Id: OTP-17202 Aux Id: PR-4516

• Fix bug where complex seq_trace tokens (that is lists, tuples, maps etc) could becomes corrupted by the GC. The bug was introduced in OTP-21.

  Own Id: OTP-17209 Aux Id: PR-3039

• When running Xref in the modules mode, the Debugger application would show up as a depency for the Kernel applications.

  Own Id: OTP-17223 Aux Id: GH-4546, PR-4554

Improvements and New Features

• erl_epmd (the epmd client) will now try to reconnect to the local EPMD if the connection is broken.

  Own Id: OTP-17178 Aux Id: PR-3003

1.3  Kernel 7.2.1

Fixed Bugs and Malfunctions

• When using the DNS resolver option servfail_retry_timeout it did not honour the overall call time-out in e.g inet_res:getbyname/3. This misbehaviour has now been fixed. Also, the servfail_retry_timeout behaviour has been improved to only be enforced for servers that gives a servfail answer.

  Own Id: OTP-12960 Aux Id: ERIERL-598, PR-4509

1.4  Kernel 7.2

Fixed Bugs and Malfunctions

• The apply call's in logger.hrl are now called with erlang prefix to avoid clashed with local apply/3 functions.

  Own Id: OTP-16976 Aux Id: PR-2807

• Fix memory leak in pg.

  Own Id: OTP-17034 Aux Id: PR-2866

• Fix crash in logger_proxy due to stray gen_server:call replies not being handled. The stray replies come when logger is under heavy load and the flow control mechanism is reaching its limit.

  Own Id: OTP-17038

• Fixed a bug in erl_epmd:names() that caused it to return the illegal return value noport instead of {error, Reason} where Reason is the actual error reason. This bug also propagated to net_adm:names().

  This bug was introduced in kernel version 7.1 (OTP 23.1).

  Own Id: OTP-17054 Aux Id: ERL-1424

Improvements and New Features

• Add export of some resolver documented types.

  Own Id: OTP-16954 Aux Id: ERIERL-544

• Add configurable retry timeout for resolver lookups.

  Own Id: OTP-16956 Aux Id: ERIERL-547

• gen_server:multi_call() has been optimized in the special case of only calling the local node with timeout set to infinity.

  Own Id: OTP-17058 Aux Id: PR-2887

1.5  Kernel 7.1

Fixed Bugs and Malfunctions

• A fallback has been implemented for file:sendfile when using inet_backend socket

  Own Id: OTP-15187 Aux Id: ERL-1293

• Make default TCP distribution honour option backlog in inet_dist_listen_options.

  Own Id: OTP-16694 Aux Id: PR-2625

• Raw option handling for the experimental gen_tcp_socket backend was broken so that all raw options were ignored by for example gen_tcp:listen/2, a bug that now has been fixed. Reported by Jan Uhlig.

  Own Id: OTP-16743 Aux Id: ERL-1287

• Accept fails with inet-backend socket.

  Own Id: OTP-16748 Aux Id: ERL-1284

• Fixed various minor errors in the socket backend of gen_tcp.

  Own Id: OTP-16754

• Correct disk_log:truncate/1 to count the header. Also correct the documentation to state that disk_log:truncate/1 can be used with external disk logs.

  Own Id: OTP-16768 Aux Id: ERL-1312

• Fix erl_epmd:port_please/2,3 type specs to include all possible error values.

  Own Id: OTP-16783

• Fix erl -erl_epmd_port to work properly. Before this fix it did not work at all.

  Own Id: OTP-16785

• Fix typespec for internal function erlang:seq_trace_info/1 to allow term() as returned label. This in turn fixes so that calls to seq_trace:get_token/1 can be correctly analyzer by dialyzer.

  Own Id: OTP-16823 Aux Id: PR-2722

• Fix erroneous double registration of processes in pg when distribution is dynamically started.

  Own Id: OTP-16832 Aux Id: PR-2738

Improvements and New Features

• Make (use of) the socket registry optional (still enabled by default). Its now possible to build OTP with the socket registry turned off, turn it off by setting an environment variable and controlling in runtime (via function calls and arguments when creating sockets).

  Own Id: OTP-16763

• erl -remsh nodename no longer requires the hostname to be given when used together with dynamic nodenames.

  Own Id: OTP-16784

1.6  Kernel 7.0

Fixed Bugs and Malfunctions

• Fix race condition during shutdown when shell_history is enabled. The race condition would trigger crashes in disk_log.

  Own Id: OTP-16008 Aux Id: PR-2302

• Fix the Erlang distribution to handle the scenario when a node connects that can handle message fragmentation but can not handle the atom cache. This bug only affects users that have implemented a custom distribution carrier. It has been present since OTP-21.

  The DFLAG_FRAGMENT distribution flag was added to the set of flags that can be rejected by a distribution implementation.

  Own Id: OTP-16284

• Fix bug where a binary was not allowed to be the format string in calls to logger:log.

  Own Id: OTP-16395 Aux Id: PR-2444

• Fix bug where logger would end up in an infinite loop when trying to log the crash of a handler or formatter.

  Own Id: OTP-16489 Aux Id: ERL-1134

• code:lib_dir/1 has been fixed to also return the lib dir for erts.

  This is been marked as an incompatibility for any application that depended on {error,bad_name} to be returned for erts.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-16502

• The application stop/1 callback was not called if the application master of the application terminated.

  Own Id: OTP-16504 Aux Id: PR-2328

• Fix bug in application:loaded_applications/0 that could cause it to fail with badarg if for example a concurrent upgrade/downgrade is running.

  Own Id: OTP-16627 Aux Id: PR-2601

Improvements and New Features

• A new module erpc has been introduced in the kernel application. The erpc module implements an enhanced subset of the operations provided by the rpc module. Enhanced in the sense that it makes it possible to distinguish between returned value, raised exceptions, and other errors. erpc also has better performance and scalability than the original rpc implementation. This by utilizing the newly introduced spawn_request() BIF. Also the rpc module benefits from these improvements by utilizing erpc when it is possible.

  This change has been marked as a potential incompatibility since rpc:block_call() now only is guaranteed to block other block_call() operations. The documentation previously claimed that it would block all rpc operations. This has however never been the case. It previously did not block node-local block_call() operations.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-13450 Aux Id: OTP-15251

• A client node can receive its node name dynamically from the node that it first connects to. This featured can by used by

  • starting with erl -sname undefined

  • erl_interface functions ei_connect_init and friends

  • erl_call -R

  Own Id: OTP-13812

• Improved the printout of single line logger events for most of the OTP behaviours in STDLIB and Kernel. This includes proc_lib, gen_server, gen_event, gen_statem, gen_fsm, supervisor, supervisor_bridge and application.

  Improved the chars_limit and depth handling in proc_lib and when formatting of exceptions.

  Own Id: OTP-15299

• Remove usage and documentation of old requests of the I/O-protocol.

  Own Id: OTP-15695

• Directories can now be opened by file:open/2 when passing the directory option.

  Own Id: OTP-15835 Aux Id: PR-2212

• The check of whether to log or not based on the log level in logger has been optimized by using persistent_term to store the log level.

  Own Id: OTP-15948 Aux Id: PR-2356

• file:read_file_info/2 can now be used on opened files and directories.

  Own Id: OTP-15956 Aux Id: PR-2231

• The -config option to erl now can take multiple config files without repeating the -config option. Example:

  erl -config sys local

  Own Id: OTP-16148 Aux Id: PR-2373

• Improved node connection setup handshake protocol. Made possible to agree on protocol version without dependence on epmd or other prior knowledge of peer node version. Also added exchange of node incarnation ("creation") values and expanded the distribution capability flag field from 32 to 64 bits.

  Own Id: OTP-16229

• The possibility to run Erlang distribution without relying on EPMD has been extended. To achieve this a couple of new options to the inet distribution has been added.

  -dist_listen false

  Setup the distribution channel, but do not listen for incoming connection. This is useful when you want to use the current node to interact with another node on the same machine without it joining the entire cluster.

  -erl_epmd_port Port

  Configure a default port that the built-in EPMD client should return. This allows the local node to know the port to connect to for any other node in the cluster.

  The erl_epmd callback API has also been extended to allow returning -1 as the creation which means that a random creation will be created by the node.

  In addition a new callback function called listen_port_please has been added that allows the callback to return which listen port the distribution should use. This can be used instead of inet_dist_listen_min/max if the listen port is to be fetched from an external service.

  Own Id: OTP-16250

• A first EXPERIMENTAL module that is a socket backend to gen_tcp and inet has been implemented. Others will follow. Feedback will be appreciated.

  Own Id: OTP-16260 Aux Id: OTP-15403

• The new experimental socket module has been moved to the Kernel application.

  Own Id: OTP-16312

• Replace usage of deprecated function in the group module.

  Own Id: OTP-16345

• Minor updates due to the new spawn improvements made.

  Own Id: OTP-16368 Aux Id: OTP-15251

• Update of sequential tracing to also support other information transfers than message passing.

  Own Id: OTP-16370 Aux Id: OTP-15251, OTP-15232

• code:module_status/1 now accepts a list of modules. code:module_status/0, which returns the statuses for all loaded modules, has been added.

  Own Id: OTP-16402

• filelib:wildcard/1,2 is now twice as fast when a double star (**) is part of the pattern.

  Own Id: OTP-16419

• A new implementation of distributed named process groups has been introduced. It is available in the pg module.

  Note that this pg module only has the name in common with the experimental pg module that was present in stdlib up until OTP 17.

  Thanks to Maxim Fedorov for the implementation.

  Own Id: OTP-16453 Aux Id: PR-2524

• The pg2 module has been deprecated. It has also been scheduled for removal in OTP 24.

  You are advised to replace the usage of pg2 with the newly introduced pg module. pg has a similar API, but with a more scalable implementation.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-16455

• Refactored the internal handling of deprecated and removed functions.

  Own Id: OTP-16469

• The internal hosts file resolver cache inet_hosts has been rewritten to behave better when the hosts file changes. For example the cache is updated per entry instead of cleared and reloaded so lookups do not temporarily fail during reloading, and; when multiple processes simultaneously request reload these are now folded into one instead of all done in sequence. Reported and first solution suggestion by Maxim Fedorov.

  Own Id: OTP-16487 Aux Id: PR-2516

• Add code:all_available/0 that can be used to get all available modules.

  Own Id: OTP-16494

• As of OTP 23, the distributed disk_log feature has been deprecated. It has also been scheduled for removal in OTP 24.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-16495

• Add the function code:fetch_docs/1 for fetching embedded documentation for aa Erlang module.

  Own Id: OTP-16499

• Improve configure for the net nif, which should increase portability.

  Own Id: OTP-16530 Aux Id: OTP-16464

• socket: Socket counters and socket global counters are now represented as maps (instead of property lists).

  Own Id: OTP-16535

• The experimental socket module has gotten restrictions removed so now the 'seqpacket' socket type should work for any communication domain (protocol family) where the OS supports it, typically the Unix Domain.

  Own Id: OTP-16550 Aux Id: ERIERL-476

• Allow using custom IO devices in logger_std_h.

  Own Id: OTP-16563 Aux Id: PR-2523

• Added file:del_dir_r/1 which deletes a directory together with all of its contents, similar to rm -rf on Unix systems.

  Own Id: OTP-16570 Aux Id: PR-2565

• socket: By default the socket options rcvtimeo and sndtimeo are now disabled. To enable these, OTP now has to be built with the configure option --enable-esock-rcvsndtimeo

  Own Id: OTP-16620

• The experimental gen_tcp compatibility code utilizing the socket module could loose buffered data when receiving a specified number of bytes. This bug has been fixed. Reported by Maksim Lapshin on bugs.erlang.org ERL-1234

  Own Id: OTP-16632 Aux Id: ERL-1234

1.7  Kernel 6.5.2.2

Fixed Bugs and Malfunctions

• When running Xref in the modules mode, the Debugger application would show up as a depency for the Kernel applications.

  Own Id: OTP-17223 Aux Id: GH-4546, PR-4554

1.8  Kernel 6.5.2.1

Fixed Bugs and Malfunctions

• Fix bug in application:loaded_applications/0 that could cause it to fail with badarg if for example a concurrent upgrade/downgrade is running.

  Own Id: OTP-16627 Aux Id: PR-2601

1.9  Kernel 6.5.2

Fixed Bugs and Malfunctions

• The DNS resolver `inet_res` has been fixed to return the last intermediate error when subsequent requests times out.

  Own Id: OTP-16414 Aux Id: ERIERL-452

• The prim_net nif (net/kernel) made use of an undefined atom, notsup. This has now been corrected.

  Own Id: OTP-16440

• Fix a crash when attempting to log faults when loading files during early boot.

  Own Id: OTP-16491

• Fix crash in logger when logging to a remote node during boot.

  Own Id: OTP-16493 Aux Id: ERIERL-459

Improvements and New Features

• Improved net_kernel debug functionality.

  Own Id: OTP-16458 Aux Id: PR-2525

1.10  Kernel 6.5.1

Fixed Bugs and Malfunctions

• The 'socket state' info provided by the inet info function has been improved

  Own Id: OTP-16043 Aux Id: ERL-1036

• Fix bug where logger would crash when starting when a very large log file needed to be rotated and compressed.

  Own Id: OTP-16145 Aux Id: ERL-1034

• Fixed a bug causing actual nodedown reason reported by net_kernel:monitor_nodes(true, [nodedown_reason]) to be lost and replaced by the reason killed.

  Own Id: OTP-16216

• The documentation for rpc:call/4,5/ has been updated to describe what happens when the called function throws or return an 'EXIT' tuple.

  Own Id: OTP-16279 Aux Id: ERL-1066

1.11  Kernel 6.5

Fixed Bugs and Malfunctions

• The type specification for gen_sctp:connect/4,5 has been corrected.

  Own Id: OTP-15344 Aux Id: ERL-947

• Extra -mode flags given to erl are ignored with a warning.

  Own Id: OTP-15852

• Fix type spec for seq_trace:set_token/2.

  Own Id: OTP-15858 Aux Id: ERL-700

• logger:compare_levels/2 would fail with a badarg exception if given the values all or none as any of the parameters. This is now corrected.

  Own Id: OTP-15942 Aux Id: PR-2301

• Fix bug where the log file in logger_std_h would not be closed when the inode of the file changed. This would in turn cause a file descriptor leak when tools like logrotate are used.

  Own Id: OTP-15997 Aux Id: PR-2331

• Fix a race condition in the debugging function net_kernel:nodes_info/0.

  Own Id: OTP-16022

• Fix race condition when closing a file opened in compressed or delayed_write mode.

  Own Id: OTP-16023

Improvements and New Features

• The possibility to send ancillary data, in particular the TOS field, has been added to gen_udp:send/4,5.

  Own Id: OTP-15747 Aux Id: ERIERL-294

• If the log file was given with relative path, the standard logger handler (logger_std_h) would store the file name with relative path. If the current directory of the node was later changed, a new file would be created relative the new current directory, potentially failing with an enoent if the new directory did not exist. This is now corrected and logger_std_h always stores the log file name as an absolute path, calculated from the current directory at the time of the handler startup.

  Own Id: OTP-15850

• Support local sockets with inet:i/0.

  Own Id: OTP-15935 Aux Id: PR-2299

1.12  Kernel 6.4.1

Fixed Bugs and Malfunctions

• user/user_drv could respond to io requests before they had been processed, which could cause data to be dropped if the emulator was halted soon after a call to io:format/2, such as in an escript.

  Own Id: OTP-15805

1.13  Kernel 6.4

Fixed Bugs and Malfunctions

• Fix so that when multiple -sname or -name are given to erl the first one is chosen. Before this fix distribution was not started at all when multiple name options were given.

  Own Id: OTP-15786 Aux Id: ERL-918

• Fix inet_res configuration pointing to non-existing files to work again. This was broken in KERNEL-6.3 (OTP-21.3).

  Own Id: OTP-15806

Improvements and New Features

• A simple socket API is provided through the socket module. This is a low level API that does *not* replace gen_[tcp|udp|sctp]. It is intended to *eventually* replace the inet driver, but not the high level gen-modules (gen_tcp, gen_udp and gen_sctp). It also provides a basic API that facilitates the implementation of other protocols, that is TCP, UDP and SCTP.

  Known issues are; No support for the Windows OS (currently).

  Own Id: OTP-14831

• Improved the documentation for the linger option.

  Own Id: OTP-15491 Aux Id: PR-2019

• Global no longer tries more than once when connecting to other nodes.

  Own Id: OTP-15607 Aux Id: ERIERL-280

• The dist messages EXIT, EXIT2 and MONITOR_DOWN have been updated with new versions that send the reason term as part of the payload of the message instead of as part of the control message.

  The old versions are still present and can be used when communicating with nodes that don't support the new versions.

  Own Id: OTP-15611

• Kernel configuration parameter start_distribution = boolean() is added. If set to false, the system is started with all distribution functionality disabled. Defaults to true.

  Own Id: OTP-15668 Aux Id: PR-2088

• In OTP-21.3, a warning was introduced for duplicated applications/keys in configuration. This warning would be displayed both when the configuration was given as a file on system start, and during runtime via application:set_env/1,2.

  The warning is now changed to a badarg exception in application:set_env/1,2. If the faulty configuration is given in a configuration file on system start, the startup will fail.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-15692 Aux Id: PR-2170

1.14  Kernel 6.3.1.3

Fixed Bugs and Malfunctions

• Fix bug where the log file in logger_std_h would not be closed when the inode of the file changed. This would in turn cause a file descriptor leak when tools like logrotate are used.

  Own Id: OTP-15997 Aux Id: PR-2331

1.15  Kernel 6.3.1.2

Improvements and New Features

• The possibility to send ancillary data, in particular the TOS field, has been added to gen_udp:send/4,5.

  Own Id: OTP-15747 Aux Id: ERIERL-294

1.16  Kernel 6.3.1.1

Fixed Bugs and Malfunctions

• Fix type spec for seq_trace:set_token/2.

  Own Id: OTP-15858 Aux Id: ERL-700

1.17  Kernel 6.3.1

Fixed Bugs and Malfunctions

• Fixed a performance regression when reading files opened with the compressed flag.

  Own Id: OTP-15706 Aux Id: ERIERL-336

1.18  Kernel 6.3

Fixed Bugs and Malfunctions

• If for example the /etc/hosts did not come into existence until after the kernel application had started, its content was never read. This bug has now been corrected.

  Own Id: OTP-14702 Aux Id: PR-2066

• Fix bug where doing seq_trace:reset_trace() while another process was doing a garbage collection could cause the run-time system to segfault.

  Own Id: OTP-15490

• Fix erl_epmd:port_please spec to include atom() and string().

  Own Id: OTP-15557 Aux Id: PR-2117

• The Logger handler logger_std_h now keeps track of the inode of its log file in order to re-open the file if the inode changes. This may happen, for instance, if the log file is opened and saved by an editor.

  Own Id: OTP-15578 Aux Id: ERL-850

• When user specific file modes are given to the logger handler logger_std_h, they were earlier accepted without any control. This is now changes, so Logger will adjust the file modes as follows:

  - If raw is not found in the list, it is added.
  - If none of write, append or exclusive are found in the list, append is added.
  - If none of delayed_write or {delayed_write,Size,Delay} are found in the list, delayed_write is added.

  Own Id: OTP-15602

Improvements and New Features

• The standard logger handler, logger_std_h, now has a new internal feature for log rotation. The rotation scheme is as follows:

  The log file to which the handler currently writes always has the same name, i.e. the name which is configured for the handler. The archived files have the same name, but with extension ".N", where N is an integer. The newest archive has extension ".0", and the oldest archive has the highest number.

  The size at which the log file is rotated, and the number of archive files that are kept, is specified with the handler specific configuration parameters max_no_bytes and max_no_files respectively.

  Archives can be compressed, in which case they get a ".gz" file extension after the integer. Compression is specified with the handler specific configuration parameter compress_on_rotate.

  Own Id: OTP-15479

• The new functions logger:i/0 and logger:i/1 are added. These provide the same information as logger:get_config/0 and other logger:get_*_config functions, but the information is more logically sorted and more readable.

  Own Id: OTP-15600

• Logger is now protected against overload due to massive amounts of log events from the emulator or from remote nodes.

  Own Id: OTP-15601

• Logger now uses os:system_time/1 instead of erlang:system_time/1 to generate log event timestamps.

  Own Id: OTP-15625

• Add functions application:set_env/1,2 and application:set_env/2. These take a list of application configuration parameters, and the behaviour is equivalent to calling application:set_env/4 individually for each application/key combination, except it is more efficient.

  set_env/1,2 warns about duplicated applications or keys. The warning is also emitted during boot, if applications or keys are duplicated within one configuration file, e.g. sys.config.

  Own Id: OTP-15642 Aux Id: PR-2164

• Handler specific configuration parameters for the standard handler logger_std_h are changed to be more intuitive and more similar to the disk_log handler.

  Earlier there was only one parameter, type, which could have the values standard_io, standard_error, {file,FileName} or {file,FileName,Modes}.

  This is now changed, so the following parameters are allowed:

  type = standard_io | standard_error | file
  file = file:filename()
  modes = [file:mode()]

  All parameters are optional. type defaults to standard_io, unless a file name is given, in which case it defaults to file. If type is set to file, the file name defaults to the same as the handler id.

  The potential incompatibility is that logger:get_config/0 and logger:get_handler_config/1 now returns the new parameters, even if the configuration was set with the old variant, e.g. #{type=>{file,FileName}}.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-15662

• The new configuration parameter file_check is added to the Logger handler logger_std_h. This parameter specifies how long (in milliseconds) the handler may wait before checking if the log file still exists and the inode is the same as when it was opened.

  The default value is 0, which means that this check is done prior to each write operation. Setting a higher number may improve performance, but adds the risk of loosing log events.

  Own Id: OTP-15663

1.19  Kernel 6.2.1

Fixed Bugs and Malfunctions

• Setting the recbuf size of an inet socket the buffer is also automatically increased. Fix a bug where the auto adjustment of inet buffer size would be triggered even if an explicit inet buffer size had already been set.

  Own Id: OTP-15651 Aux Id: ERIERL-304

1.20  Kernel 6.2

Fixed Bugs and Malfunctions

• A new function, logger:update_handler_config/3 is added, and the handler callback changing_config now has a new argument, SetOrUpdate, which indicates if the configuration change comes from set_handler_config/2,3 or update_handler_config/2,3.

  This allows the handler to consistently merge the new configuration with the old (if the change comes from update_handler_config/2,3) or with the default (if the change comes from set_handler_config/2,3).

  The built-in handlers logger_std_h and logger_disk_log_h are updated accordingly. A bug which could cause inconsistency between the handlers' internal state and the stored configuration is also corrected.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-15364

• Fix fallback when custom erl_epmd client does not implement address_please.

  Own Id: OTP-15388 Aux Id: PR-1983

• The logger ets table did not have the read_concurrency option. This is now added.

  Own Id: OTP-15453 Aux Id: ERL-782

• During system start, logger has a simple handler which prints to stdout. After the kernel supervision is started, this handler is removed and replaced by the default handler. Due to a bug, logger earlier issued a debug printout saying it received an unexpected message, which was the EXIT message from the simple handler's process. This is now corrected. The simple handler's process now unlinks from the logger process before terminating.

  Own Id: OTP-15466 Aux Id: ERL-788

• The logger handler logger_std_h would not re-create it's log file if it was removed. Due to this it could not be used with tools like 'logrotate'. This is now corrected.

  Own Id: OTP-15469

Improvements and New Features

• A function inet:getifaddrs/1 that takes a list with a namespace option has been added, for platforms that support that feature, for example Linux (only?).

  Own Id: OTP-15121 Aux Id: ERIERL-189, PR-1974

• Added the nopush option for TCP sockets, which corresponds to TCP_NOPUSH on *BSD and TCP_CORK on Linux.

  This is also used internally in file:sendfile to reduce latency on subsequent send operations.

  Own Id: OTP-15357 Aux Id: ERL-698

• Optimize handling of send_delay for tcp sockes to better work with the new pollthread implementation introduced in OTP-21.

  Own Id: OTP-15471 Aux Id: ERIERL-229

1.21  Kernel 6.1.1

Fixed Bugs and Malfunctions

• Fix bug causing net_kernel process crash on connection attempt from node with name identical to local node.

  Own Id: OTP-15438 Aux Id: ERL-781

1.22  Kernel 6.1

Fixed Bugs and Malfunctions

• The values all and none are documented as valid value for the Kernel configuration parameter logger_level, but would cause a crash during node start. This is now corrected.

  Own Id: OTP-15143

• Fix some potential buggy behavior in how ticks are sent on inter node distribution connections. Tick is now sent to c-node even if there are unsent buffered data, as c-nodes need ticks in order to send reply ticks. The amount of sent data was also calculated wrongly when ticks were suppressed due to unsent buffered data.

  Own Id: OTP-15162 Aux Id: ERIERL-191

• Non semantic change in dist_util.erl to silence dialyzer warning.

  Own Id: OTP-15170

• Fixed net_kernel:connect_node(node()) to return true (and do nothing) as it always has before OTP-21.0. Also documented this successful "self connect" as the expected behavior.

  Own Id: OTP-15182 Aux Id: ERL-643

• The single_line option on logger_formatter would in some cases add an unwanted comma after the association arrows in a map. This is now corrected.

  Own Id: OTP-15228

• Improved robustness of distribution connection setup. In OTP-21.0 a truly asynchronous connection setup was introduced. This is further improvement on that work to make the emulator more robust and also be able to recover in cases when involved Erlang processes misbehave.

  Own Id: OTP-15297 Aux Id: OTP-15279, OTP-15280

Improvements and New Features

• A new macro, ?LOG(Level,...), is added. This is equivalent to the existing ?LOG_<LEVEL>(...) macros.

  A new variant of Logger report callback is added, which takes an extra argument containing options for size limiting and line breaks. Module proc_lib in STDLIB uses this for crash reports.

  Logger configuration is now checked a bit more for errors.

  Own Id: OTP-15132

• The socket options recvtos, recvttl, recvtclass and pktoptions have been implemented in the socket modules. See the documentation for the gen_tcp, gen_udp and inet modules. Note that support for these in the runtime system is platform dependent. Especially for pktoptions which is very Linux specific and obsoleted by the RFCs that defined it.

  Own Id: OTP-15145 Aux Id: ERIERL-187

• Add logger:set_application_level/2 for setting the logger level of all modules in one application.

  Own Id: OTP-15146

1.23  Kernel 6.0.1

Fixed Bugs and Malfunctions

• Fixed bug in net_kernel that could cause an emulator crash if certain connection attempts failed. Bug exists since kernel-6.0 (OTP-21.0).

  Own Id: OTP-15280 Aux Id: ERIERL-226, OTP-15279

1.24  Kernel 6.0

Fixed Bugs and Malfunctions

• Clarify the documentation of rpc:multicall/5.

  Own Id: OTP-10551

• The DNS resolver when getting econnrefused from a server retained an invalid socket so look up towards the next server(s) also failed.

  Own Id: OTP-13133 Aux Id: PR-1557

• No resolver backend returns V4Mapped IPv6 addresses any more. This was inconsistent before, some did, some did not. To facilitate working with such addresses a new function inet:ipv4_mapped_ipv6_address/1 has been added.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-13761 Aux Id: ERL-503

• The type specifications for file:posix/0 and inet:posix/0 have been updated according to which errors file and socket operations should be able to return.

  Own Id: OTP-14019 Aux Id: ERL-550

• Fix name resolving in IPv6 only environments when doing the initial distributed connection.

  Own Id: OTP-14501

• File operations used to accept filenames containing null characters (integer value zero). This caused the name to be truncated and in some cases arguments to primitive operations to be mixed up. Filenames containing null characters inside the filename are now rejected and will cause primitive file operations to fail.

  Also environment variable operations used to accept names and values of environment variables containing null characters (integer value zero). This caused operations to silently produce erroneous results. Environment variable names and values containing null characters inside the name or value are now rejected and will cause environment variable operations to fail.

  Primitive environment variable operations also used to accept the $= character in environment variable names causing various problems. $= characters in environment variable names are now also rejected.

  Also os:cmd/1 now reject null characters inside its command.

  erlang:open_port/2 will also reject null characters inside the port name from now on.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-14543 Aux Id: ERL-370

• os:putenv and os:getenv no longer access the process environment directly and instead work on a thread-safe emulation. The only observable difference is that it's not kept in sync with libc getenv(3) / putenv(3), so those who relied on that behavior in drivers or NIFs will need to add manual synchronization.

  On Windows this means that you can no longer resolve DLL dependencies by modifying the PATH just before loading the driver/NIF. To make this less of a problem, the emulator now adds the target DLL's folder to the DLL search path.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-14666

• Fixed connection tick toward primitive hidden nodes (erl_interface) that could cause faulty tick timeout in rare cases when payload data is sent to hidden node but not received.

  Own Id: OTP-14681

• Make group react immediately on an EXIT-signal from shell in e.g ssh.

  Own Id: OTP-14991 Aux Id: PR1705

• Calls to gen_tcp:send/2 on closed sockets now returns {error, closed} instead of {error,enotconn}.

  Own Id: OTP-15001

• The included_applications key are no longer duplicated as application environment variable. Earlier, the included applications could be read both with application:get[_all]_env(...) and application:get[_all]_key(...) functions. Now, it can only be read with application:get[_all]_key(...).

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-15071

• Owner and group changes through file:write_file_info, file:change_owner, and file:change_group will no longer report success on permission errors.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-15118

Improvements and New Features

• A new logging API is added to Erlang/OTP, see the logger(3) manual page, and section Logging in the Kernel User's Guide.

  Calls to error_logger are automatically redirected to the new API, and legacy error logger event handlers can still be used. It is, however, recommended to use the Logger API directly when writing new code.

  Notice the following potential incompatibilities:

  • Kernel configuration parameters error_logger still works, but is overruled if the default handler's output destination is configured with Kernel configuration parameter logger.

    In general, parameters for configuring error logger are overwritten by new parameters for configuring Logger.

  • The concept of SASL error logging is deprecated, meaning that by default the SASL application does not affect which log events are logged.

    By default, supervisor reports and crash reports are logged by the default Logger handler started by Kernel, and end up at the same destination (terminal or file) as other standard log event from Erlang/OTP.

    Progress reports are not logged by default, but can be enabled by setting the primary log level to info, for example with the Kernel configuration parameter logger_level.

    To obtain backwards compatibility with the SASL error logging functionality from earlier releases, set Kernel configuration parameter logger_sasl_compatible to true. This prevents the default Logger handler from logging any supervisor-, crash-, or progress reports. Instead, SASL adds a separate Logger handler during application start, which takes care of these log events. The SASL configuration parameters sasl_error_logger and sasl_errlog_type specify the destination (terminal or file) and severity level to log for these events.

  Since Logger is new in Erlang/OTP 21.0, we do reserve the right to introduce changes to the Logger API and functionality in patches following this release. These changes might or might not be backwards compatible with the initial version.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-13295

• The function inet:i/0 has been documented.

  Own Id: OTP-13713 Aux Id: PR-1645

• Typespecs for netns and bind_to_device options have been added to gen_tcp, gen_udp and gen_sctp functions.

  Own Id: OTP-14359 Aux Id: PR-1816

• New functionality for implementation of alternative carriers for the Erlang distribution has been introduced. This mainly consists of support for usage of distribution controller processes (previously only ports could be used as distribution controllers). For more information see ERTS User's Guide ➜ How to implement an Alternative Carrier for the Erlang Distribution ➜ Distribution Module.

  Own Id: OTP-14459

• seq_trace labels may now be any erlang term.

  Own Id: OTP-14899

• The SSL distribution protocol -proto inet_tls has stopped setting the SSL option server_name_indication. New verify funs for client and server in inet_tls_dist has been added, not documented yet, that checks node name if present in peer certificate. Usage is still also yet to be documented.

  Own Id: OTP-14969 Aux Id: OTP-14465, ERL-598

• Changed timeout of gen_server calls to auth server from default 5 seconds to infinity.

  Own Id: OTP-15009 Aux Id: ERL-601

• The callback module passed as -epmd_module to erl has been expanded to be able to do name and port resolving.

  Documentation has also been added in the erl_epmd reference manual and ERTS User's Guide How to Implement an Alternative Node Discovery for Erlang Distribution.

  Own Id: OTP-15086 Aux Id: PR-1694

• Included config file specified with relative path in sys.config are now first searched for relative to the directory of sys.config itself. If not found, it is also searched for relative to the current working directory. The latter is for backwards compatibility.

  Own Id: OTP-15137 Aux Id: PR-1838

1.25  Kernel 5.4.3.2

Fixed Bugs and Malfunctions

• Non semantic change in dist_util.erl to silence dialyzer warning.

  Own Id: OTP-15170

1.26  Kernel 5.4.3.1

Fixed Bugs and Malfunctions

• Fix some potential buggy behavior in how ticks are sent on inter node distribution connections. Tick is now sent to c-node even if there are unsent buffered data, as c-nodes need ticks in order to send reply ticks. The amount of sent data was calculated wrongly when ticks where suppressed due to unsent buffered data.

  Own Id: OTP-15162 Aux Id: ERIERL-191

1.27  Kernel 5.4.3

Fixed Bugs and Malfunctions

• Correct a few contracts.

  Own Id: OTP-14889

• Reject loading modules with names containing directory separators ('/' or '\' on Windows).

  Own Id: OTP-14933 Aux Id: ERL-564, PR-1716

• Fix bug in handling of os:cmd/2 option max_size on windows.

  Own Id: OTP-14940

1.28  Kernel 5.4.2

Fixed Bugs and Malfunctions

• Add os:cmd/2 that takes an options map as the second argument.

  Add max_size as an option to os:cmd/2 that control the maximum size of the result that os:cmd/2 will return.

  Own Id: OTP-14823

1.29  Kernel 5.4.1

Fixed Bugs and Malfunctions

• Refactored an internal API.

  Own Id: OTP-14784

1.30  Kernel 5.4

Fixed Bugs and Malfunctions

• Processes which did output after switching jobs (Ctrl+G) could be left forever stuck in the io request.

  Own Id: OTP-14571 Aux Id: ERL-472

Improvements and New Features

• Lock counting can now be fully toggled at runtime in the lock counting emulator (-emu_type lcnt). Everything is enabled by default to match the old behavior, but specific categories can be toggled at will with minimal runtime overhead when disabled. Refer to the documentation on lcnt:rt_mask/1 for details.

  Own Id: OTP-13170

• lcnt:collect and lcnt:clear will no longer block all other threads in the runtime system.

  Own Id: OTP-14412

• General Unicode improvements.

  Own Id: OTP-14462

1.31  Kernel 5.3.1

Fixed Bugs and Malfunctions

• The documentation for the 'quiet' option in disk_log:open/1 had an incorrect default value.

  Own Id: OTP-14498

1.32  Kernel 5.3

Fixed Bugs and Malfunctions

• Function inet:ntoa/1 has been fixed to return lowercase letters according to RFC 5935 that has been approved after this function was written. Previously uppercase letters were returned so this may be a backwards incompatible change depending on how the returned address string is used.

  Function inet:parse_address/1 has been fixed to accept %-suffixes on scoped addresses. The addresses does not work yet, but gives no parse errors.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-13006 Aux Id: ERIERL-20, ERL-429

• Fix bug where gethostname would incorrectly fail with enametoolong on Linux.

  Own Id: OTP-14310

• Fix bug causing code:is_module_native to falsely return true when local call trace is enabled for the module.

  Own Id: OTP-14390

• Add early reject of invalid node names from distributed nodes.

  Own Id: OTP-14426

Improvements and New Features

• Since Unicode is now allowed in atoms an extra check is needed for node names, which are restricted to Latin-1.

  Own Id: OTP-13805

• Replaced usage of deprecated symbolic time unit representations.

  Own Id: OTP-13831 Aux Id: OTP-13735

• file:write_file(Name, Data, [raw]) would turn Data into a single binary before writing. This meant it could not take advantage of the writev() system call if it was given a list of binaries and told to write with raw mode.

  Own Id: OTP-13909

• The performance of the disk_log has been somewhat improved in some corner cases (big items), and the documentation has been clarified.

  Own Id: OTP-14057 Aux Id: PR-1245

• Functions for detecting changed code has been added. code:modified_modules/0 returns all currently loaded modules that have changed on disk. code:module_status/1 returns the status for a module. In the shell and in c module, mm/0 is short for code:modified_modules/0, and lm/0 reloads all currently loaded modules that have changed on disk.

  Own Id: OTP-14059

• Introduce an event manager in Erlang to handle OS signals. A subset of OS signals may be subscribed to and those are described in the Kernel application.

  Own Id: OTP-14186

• Sockets can now be bound to device (SO_BINDTODEVICE) on platforms where it is supported.

  This has been implemented e.g to support VRF-Lite under Linux; see VRF , and GitHub pull request #1326.

  Own Id: OTP-14357 Aux Id: PR-1326

• Added option to store shell_history on disk so that the history can be reused between sessions.

  Own Id: OTP-14409 Aux Id: PR-1420

• The size of crash reports created by gen_server, gen_statem and proc_lib is limited with aid of the Kernel application variable error_logger_format_depth. The purpose is to limit the size of the messages sent to the error_logger process when processes with huge message queues or states crash.

  The crash report generated by proc_lib includes the new tag message_queue_len. The neighbour report also includes the new tag current_stacktrace. Finally, the neighbour report no longer includes the tags messages and dictionary.

  The new function error_logger:get_format_depth/0 can be used to retrieve the value of the Kernel application variable error_logger_format_depth.

  Own Id: OTP-14417

• One of the ETS tables used by the global module is created with {read_concurrency, true} in order to reduce contention.

  Own Id: OTP-14419

• Warnings have been added to the relevant documentation about not using un-secure distributed nodes in exposed environments.

  Own Id: OTP-14425

1.33  Kernel 5.2

Fixed Bugs and Malfunctions

• Fix a race during cleanup of os:cmd that would cause os:cmd to hang indefinitely.

  Own Id: OTP-14232 Aux Id: seq13275

Improvements and New Features

• The functions in the 'file' module that take a list of paths (e.g. file:path_consult/2) will now continue to search in the path if the path contains something that is not a directory.

  Own Id: OTP-14191

• Two OTP processes that are known to receive many messages are 'rex' (used by 'rpc') and 'error_logger'. Those processes will now store unprocessed messages outside the process heap, which will potentially decrease the cost of garbage collections.

  Own Id: OTP-14192

1.34  Kernel 5.1.1

Fixed Bugs and Malfunctions

• code:add_pathsa/1 and command line option -pa both revert the given list of directories when adding it at the beginning of the code path. This is now documented.

  Own Id: OTP-13920 Aux Id: ERL-267

• Add lost runtime dependency to erts-8.1. This should have been done in kernel-5.1 (OTP-19.1) as it cannot run without at least erts-8.1 (OTP-19.1).

  Own Id: OTP-14003

• Type and doc for gen_{tcp,udp,sctp}:controlling_process/2 has been improved.

  Own Id: OTP-14022 Aux Id: PR-1208

1.35  Kernel 5.1

Fixed Bugs and Malfunctions

• Fix a memory leak when calling seq_trace:get_system_tracer().

  Own Id: OTP-13742

• Fix for the problem that when adding the ebin directory of an application to the code path, the code:priv_dir/1 function returns an incorrect path to the priv directory of the same application.

  Own Id: OTP-13758 Aux Id: ERL-195

• Fix code_server crash when adding code paths of two levels.

  Own Id: OTP-13765 Aux Id: ERL-194

• Respect -proto_dist switch while connection to EPMD

  Own Id: OTP-13770 Aux Id: PR-1129

• Fixed a bug where init:stop could deadlock if a process with infinite shutdown timeout (e.g. a supervisor) attempted to load code while terminating.

  Own Id: OTP-13802

• Close stdin of commands run in os:cmd. This is a backwards compatibility fix that restores the behaviour of pre 19.0 os:cmd.

  Own Id: OTP-13867 Aux Id: seq13178

Improvements and New Features

• Add net_kernel:setopts/2 and net_kernel:getopts/2 to control options for distribution sockets in runtime.

  Own Id: OTP-13564

• Rudimentary support for DSCP has been implemented in the guise of a tclass socket option for IPv6 sockets.

  Own Id: OTP-13582

1.36  Kernel 5.0.2

Fixed Bugs and Malfunctions

• When calling os:cmd from a process that has set trap_exit to true an 'EXIT' message would be left in the message queue. This bug was introduced in kernel vsn 5.0.1.

  Own Id: OTP-13813

1.37  Kernel 5.0.1

Fixed Bugs and Malfunctions

• Fix a os:cmd bug where creating a background job using & would cause os:cmd to hang until the background job terminated or closed its stdout and stderr file descriptors. This bug has existed from kernel 5.0.

  Own Id: OTP-13741

1.38  Kernel 5.0

Fixed Bugs and Malfunctions

• The handling of on_load functions has been improved. The major improvement is that if a code upgrade fails because the on_load function fails, the previous version of the module will now be retained.

  Own Id: OTP-12593

• rpc:call() and rpc:block_call() would sometimes cause an exception (which was not mentioned in the documentation). This has been corrected so that {badrpc,Reason} will be returned instead.

  Own Id: OTP-13409

• On Windows, for modules that were loaded early (such as the lists module), code:which/1 would return the path with mixed slashes and backslashes, for example: "C:\\Program Files\\erl8.0/lib/stdlib-2.7/ebin/lists.beam". This has been corrected.

  Own Id: OTP-13410

• Make file:datasync use fsync instead of fdatasync on Mac OSX.

  Own Id: OTP-13411

• The default chunk size for the fallback sendfile implementation, used on platforms that do not have a native sendfile, has been decreased in order to reduce connectivity issues.

  Own Id: OTP-13444

• Large file writes (2Gb or more) could fail on some Unix platforms (for example, OS X and FreeBSD).

  Own Id: OTP-13461

• A bug has been fixed where the DNS resolver inet_res did not refresh its view of the contents of for example resolv.conf immediately after start and hence then failed name resolution. Reported and fix suggested by Michal Ptaszek in GitHUB pull req #949.

  Own Id: OTP-13470 Aux Id: Pull #969

• Fix process leak from global_group.

  Own Id: OTP-13516 Aux Id: PR-1008

• The function inet:gethostbyname/1 now honors the resolver option inet6 instead of always looking up IPv4 addresses.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-13622 Aux Id: PR-1065

• The Status argument to init:stop/1 is now sanity checked to make sure erlang:halt does not fail.

  Own Id: OTP-13631 Aux Id: PR-911

Improvements and New Features

• Add {line_delim, byte()} option to inet:setopts/2 and decode_packet/3

  Own Id: OTP-12837

• Added os:perf_counter/1.

  The perf_counter is a very very cheap and high resolution timer that can be used to timestamp system events. It does not have monoticity guarantees, but should on most OS's expose a monotonous time.

  Own Id: OTP-12908

• The os:cmd call has been optimized on unix platforms to be scale better with the number of schedulers.

  Own Id: OTP-13089

• New functions that can load multiple modules at once have been added to the 'code' module. The functions are code:atomic_load/1, code:prepare_loading/1, code:finish_loading/1, and code:ensure_modules_loaded/1.

  Own Id: OTP-13111

• The code path cache feature turned out not to be very useful in practice and has been removed. If an attempt is made to enable the code path cache, there will be a warning report informing the user that the feature has been removed.

  Own Id: OTP-13191

• When an attempt is made to start a distributed Erlang node with the same name as an existing node, the error message will be much shorter and easier to read than before. Example:

  Protocol 'inet_tcp': the name somename@somehost seems to be in use by another Erlang node

  Own Id: OTP-13294

• The output of the default error logger is somewhat prettier and easier to read. The default error logger is used during start-up of the OTP system. If the start-up fails, the output will be easier to read.

  Own Id: OTP-13325

• The functions rpc:safe_multi_server_call/2,3 that were deprecated in R12B have been removed.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-13449

• Update the error reasons in dist_util, and show them in the logs if net_kernel:verbose(1) has been called.

  Own Id: OTP-13458

• Experimental support for Unix Domain Sockets has been implemented. Read the sources if you want to try it out. Example: gen_udp:open(0, [{ifaddr,{local,"/tmp/socket"}}]). Documentation will be written after user feedback on the experimental API.

  Own Id: OTP-13572 Aux Id: PR-612

• Allow heart to be configured to not kill the previous emulator before calling the HEART_COMMAND. This is done by setting the environment variable HEART_NO_KILL to TRUE.

  Own Id: OTP-13650

1.39  Kernel 4.2

Fixed Bugs and Malfunctions

• code:load_abs([10100]) would bring down the entire runtime system and create a crash dump. Corrected to generate an error exception in the calling process.

  Also corrected specs for code loading functions and added more information in the documentation about the error reasons returned by code-loading functions.

  Own Id: OTP-9375

• gen_tcp:accept/2 was not time warp safe. This since it used the same time as returned by erlang:now/0 when calculating timeout. This has now been fixed.

  Own Id: OTP-13254 Aux Id: OTP-11997, OTP-13222

• Correct the contract for inet:getifaddrs/1.

  Own Id: OTP-13335 Aux Id: ERL-95

Improvements and New Features

• Time warp safety improvements.

  Introduced the options monotonic_timestamp, and strict_monotonic_timestamp to the trace, sequential trace, and system profile functionality. This since the already existing timestamp option is not time warp safe.

  Introduced the option safe_fixed_monotonic_time to ets:info/2 and dets:info/2. This since the already existing safe_fixed option is not time warp safe.

  Own Id: OTP-13222 Aux Id: OTP-11997

• Add validation callback for heart

  The erlang heart process may now have a validation callback installed. The validation callback will be executed, if present, before any heartbeat to heart port program. If the validation fails, or stalls, no heartbeat will be sent and the node will go down.

  With the option 'check_schedulers' heart executes a responsiveness check of the schedulers before a heartbeat is sent to the port program. If the responsiveness check fails, the heartbeat will not be performed (as intended).

  Own Id: OTP-13250

• Clarify documentation of net_kernel:allow/1

  Own Id: OTP-13299

• EPMD supports both IPv4 and IPv6

  Also affects oldest supported windows version.

  Own Id: OTP-13364

1.40  Kernel 4.1.1

Fixed Bugs and Malfunctions

• Host name lookups though inet_res, the Erlang DNS resolver, are now done case insensitively according to RFC 4343. Patch by Holger Weiß.

  Own Id: OTP-12836

• IPv6 distribution handler has been updated to share code with IPv4 so that all features are supported in IPv6 as well. A bug when using an IPv4 address as hostname has been fixed.

  Own Id: OTP-13040

• Caching of host names in the internal DNS resolver inet_res has been made character case insensitive for host names according to RFC 4343.

  Own Id: OTP-13083

• Cooked file mode buffering has been fixed so file:position/2 now works according to Posix on Posix systems i.e. when file:position/2 returns an error the file pointer is unaffected.

  The Windows system documentation, however, is unclear on this point so the documentation of file:position/2 still does not promise anything.

  Cooked file mode file:pread/2,3 and file:pwrite/2,3 have been corrected to honor character encoding like the combination of file:position/2 and file:read/2 or file:write/2 already does. This is probably not very useful since the character representation on the caller's side is latin1, period.

  Own Id: OTP-13155 Aux Id: PR#646

Improvements and New Features

• Add {line_delim, byte()} option to inet:setopts/2 and decode_packet/3

  Own Id: OTP-12837

1.41  Kernel 4.1

Improvements and New Features

• A mechanism for limiting the amount of text that the built-in error logger events will produce has been introduced. It is useful for limiting both the size of log files and the CPU time used to produce them.

  This mechanism is experimental in the sense that it may be changed if it turns out that it does not solve the problem it is supposed to solve. In that case, there may be backward incompatible improvements to this mechanism.

  See the documentation for the config parameter error_logger_format_depth in the Kernel application for information about how to turn on this feature.

  Own Id: OTP-12864

1.42  Kernel 4.0

Fixed Bugs and Malfunctions

• Fix error handling in file:read_line/1 for Unicode contents.

  Own Id: OTP-12144

• Introduce os:getenv/2 which is similar to os:getenv/1 but returns the passed default value if the required environment variable is undefined.

  Own Id: OTP-12342

• It is now possible to paste text in JCL mode (using Ctrl-Y) that has been copied in the previous shell session. Also a bug that caused the JCL mode to crash when pasting text has been fixed.

  Own Id: OTP-12673

• Ensure that each segment of an IPv6 address when parsed from a string has a maximum of 4 hex digits

  Own Id: OTP-12773

Improvements and New Features

• New BIF: erlang:get_keys/0, lists all keys associated with the process dictionary. Note: erlang:get_keys/0 is auto-imported.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-12151 Aux Id: seq12521

• The internal group to user_drv protocol has been changed to be synchronous in order to guarantee that output sent to a process implementing the user_drv protocol is printed before replying. This protocol is used by the standard_output device and the ssh application when acting as a client.

  This change changes the previous unlimited buffer when printing to standard_io and other devices that end up in user_drv to 1KB.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-12240

• The inflateInit/2 and deflateInit/6 functions now accepts a WindowBits argument equal to 8 and -8.

  Own Id: OTP-12564

• Map error logger warnings to warning messages by default.

  Own Id: OTP-12755

• Map beam error logger warnings to warning messages by default. Previously these messages were mapped to the error channel by default.

  Own Id: OTP-12781

• gen_tcp:shutdown/2 is now asynchronous

  This solves the following problems with the old implementation:

  It doesn't block when the TCP peer is idle or slow. This is the expected behaviour when shutdown() is called: the caller needs to be able to continue reading from the socket, not be prevented from doing so.

  It doesn't truncate the output. The current version of gen_tcp:shutdown/2 will truncate any outbound data in the driver queue after about 10 seconds if the TCP peer is idle of slow. Worse yet, it doesn't even inform anyone that the data has been truncated: 'ok' is returned to the caller; and a FIN rather than an RST is sent to the TCP peer.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-12797

• There are many cases where user code needs to be able to distinguish between a socket that was closed normally and one that was aborted. Setting the option {show_econnreset, true} enables the user to receive ECONNRESET errors on both active and passive sockets.

  Own Id: OTP-12843

1.43  Kernel 3.2.0.1

Fixed Bugs and Malfunctions

• The 'raw' socket option could not be used multiple times in one call to any e.g gen_tcp function because only one of the occurrences were used. This bug has been fixed, and also a small bug concerning propagating error codes from within inet:setopts/2.

  Own Id: OTP-11482 Aux Id: seq12872

1.44  Kernel 3.2

Fixed Bugs and Malfunctions

• A bug causing an infinite loop in hostname resolving has been corrected. To trigger this bug you would have to enter an bogus search method from a configuration file e.g .inetrc.

  Bug pinpointed by Emil Holmström

  Own Id: OTP-12133

• The standard_error process now handles the getopts I/O protocol request correctly and stores its encoding in the same way as standard_io.

  Also, io:put_chars(standard_error, [oops]) could previously crash the standard_error process. This is now corrected.

  Own Id: OTP-12424

Improvements and New Features

• Configuration parameters for the Kernel application that allows setting socket options for the distribution sockets have been added. See the application Kernel documentation; parameters 'inet_dist_listen_options' and 'inet_dist_connect_options'.

  Own Id: OTP-12476 Aux Id: OTP-12476

1.45  Kernel 3.1

Fixed Bugs and Malfunctions

• Make sure to install .hrl files when needed

  Own Id: OTP-12197

• Removed the undocumented application environment variable 'raw_files' from the kernel application. This variable was checked (by call to application:get_env/2) each time a raw file was to be opened in the file module.

  Own Id: OTP-12276

• A bug has been fixed when using the netns option to gen_udp, which accidentally only worked if it was the last option.

  Own Id: OTP-12314

Improvements and New Features

• Updated documentation for inet buffer size options.

  Own Id: OTP-12296

• Introduce new option 'raw' in file_info and link_info functions. This option allows the caller not to go through the file server for information about files guaranteed to be local.

  Own Id: OTP-12325

1.46  Kernel 3.0.3

Fixed Bugs and Malfunctions

• Accept inet:ip_address() in net_adm:names/1

  Own Id: OTP-12154

1.47  Kernel 3.0.2

Fixed Bugs and Malfunctions

• OTP-11850 fixed filelib:wildcard/1 to work with broken symlinks. This correction, however, introduced problems since symlinks were no longer followed for functions like filelib:ensure_dir/1, filelib:is_dir/1, filelib:file_size/1, etc. This is now corrected.

  Own Id: OTP-12054 Aux Id: seq12660

1.48  Kernel 3.0.1

Fixed Bugs and Malfunctions

• If the Config given to application_controller:change_application_data included other config files, it was only expanded for already existing (loaded) applications. If an upgrade added a new application which had config data in an included config file, the new application did not get correct config data.

  This is now changed so config data will be expanded for all applications.

  Own Id: OTP-11864

• It was allowed to re-load pre-loaded modules such as erlang, but that could cause strange and unwanted things to happen, such as call apply/3 to loop. Pre-loaded modules are now sticky by default. (Thanks to Loïc Hoguin for reporting this bug.)

  code:add_path("/ending/in/slash/") removes the trailing slash, adding /ending/in/slash to the code path. However, code:del_path("/ending/in/slash/") would fail to remove the path since it did not remove the trailing slash. This has been fixed.

  Own Id: OTP-11913

• Fix erts_debug:size/1 to handle Map sizes

  Own Id: OTP-11923

• The documentation for file:file_info/1 has been removed. The function itself was removed a long time ago.

  Own Id: OTP-11982

1.49  Kernel 3.0

Fixed Bugs and Malfunctions

• Fixed a deadlock possibility in terminate application

  Own Id: OTP-11171

• Fixed bug where sendfile would return the wrong error code for a remotely closed socket if the socket was in passive mode. (Thanks to Vincent Siliakus for reporting the bug.)

  Own Id: OTP-11614

• The new option persistent is added to application:set_env/4 and application:unset_env/3. An environment key set with the persistent option will not be overridden by the ones configured in the application resource file on load. This means persistent values will stick after the application is loaded and also on application reload. (Thanks to José Valim)

  Own Id: OTP-11708

• The spec for file:set_cwd/1 is modified to also accept binaries as arguments. This has always been allowed in the code, but it was not reflected in the spec since binaries are mostly used for raw file names. Raw file names are names that are not encoded according to file:native_name_encoding(), and these are not allowed in file:set_cwd/1. The spec is now, however, more allowing in order to avoid unnecessary dialyzer warnings. Raw file names will still fail in runtime with reason 'no_translation'. (Thanks to José Valim)

  Own Id: OTP-11787

Improvements and New Features

• heart:set_cmd/1 is updated to allow unicode code points > 255 in the given heart command

  Own Id: OTP-10843

• Dialyzer's unmatched_return warnings have been corrected.

  Own Id: OTP-10908

• Make erlang:open_port/2 spawn and spawn_executable handle unicode.

  Own Id: OTP-11105

• Erlang/OTP has been ported to the realtime operating system OSE. The port supports both smp and non-smp emulator. For details around the port and how to started see the User's Guide in the ose application.

  Note that not all parts of Erlang/OTP has been ported.

  Notable things that work are: non-smp and smp emulators, OSE signal interaction, crypto, asn1, run_erl/to_erl, tcp, epmd, distribution and most if not all non-os specific functionality of Erlang.

  Notable things that does not work are: udp/sctp, os_mon, erl_interface, binding of schedulers.

  Own Id: OTP-11334

• Add the {active,N} socket option for TCP, UDP, and SCTP, where N is an integer in the range -32768..32767, to allow a caller to specify the number of data messages to be delivered to the controlling process. Once the socket's delivered message count either reaches 0 or is explicitly set to 0 with inet:setopts/2 or by including {active,0} as an option when the socket is created, the socket transitions to passive ({active, false}) mode and the socket's controlling process receives a message to inform it of the transition. TCP sockets receive {tcp_passive,Socket}, UDP sockets receive {udp_passive,Socket} and SCTP sockets receive {sctp_passive,Socket}.

  The socket's delivered message counter defaults to 0, but it can be set using {active,N} via any gen_tcp, gen_udp, or gen_sctp function that takes socket options as arguments, or via inet:setopts/2. New N values are added to the socket's current counter value, and negative numbers can be used to reduce the counter value. Specifying a number that would cause the socket's counter value to go above 32767 causes an einval error. If a negative number is specified such that the counter value would become negative, the socket's counter value is set to 0 and the socket transitions to passive mode. If the counter value is already 0 and inet:setopts(Socket, [{active,0}]) is specified, the counter value remains at 0 but the appropriate passive mode transition message is generated for the socket.

  Thanks to Steve Vinoski

  Own Id: OTP-11368

• A call to either the garbage_collect/1 BIF or the check_process_code/2 BIF may trigger garbage collection of another processes than the process calling the BIF. The previous implementations performed these kinds of garbage collections without considering the internal state of the process being garbage collected. In order to be able to more easily and more efficiently implement yielding native code, these types of garbage collections have been rewritten. A garbage collection like this is now triggered by an asynchronous request signal, the actual garbage collection is performed by the process being garbage collected itself, and finalized by a reply signal to the process issuing the request. Using this approach processes can disable garbage collection and yield without having to set up the heap in a state that can be garbage collected.

  The garbage_collect/2, and check_process_code/3 BIFs have been introduced. Both taking an option list as last argument. Using these, one can issue asynchronous requests.

  code:purge/1 and code:soft_purge/1 have been rewritten to utilize asynchronous check_process_code requests in order to parallelize work.

  Characteristics impact: A call to the garbage_collect/1 BIF or the check_process_code/2 BIF will normally take longer time to complete while the system as a whole wont be as much negatively effected by the operation as before. A call to code:purge/1 and code:soft_purge/1 may complete faster or slower depending on the state of the system while the system as a whole wont be as much negatively effected by the operation as before.

  Own Id: OTP-11388 Aux Id: OTP-11535, OTP-11648

• Add sync option to file:open/2.

  The sync option adds the POSIX O_SYNC flag to the open system call on platforms that support the flag or its equivalent, e.g., FILE_FLAG_WRITE_THROUGH on Windows. For platforms that don't support it, file:open/2 returns {error, enotsup} if the sync option is passed in. Thank to Steve Vinoski and Joseph Blomstedt

  Own Id: OTP-11498

• The contract of inet:ntoa/1 has been corrected.

  Thanks to Max Treskin.

  Own Id: OTP-11730

1.50  Kernel 2.16.4.1

Known Bugs and Problems

• When using gen_tcp:connect and the fd option with port and/or ip, the port and ip options were ignored. This has been fixed so that if port and/or ip is specified together with fd a bind is requested for that fd. If port and/or ip is not specified bind will not be called.

  Own Id: OTP-12061

1.51  Kernel 2.16.4

Fixed Bugs and Malfunctions

• Fix the typespec for the inet:ifget/2 and inet:ifget/3 return value. Thanks to Ali Sabil.

  Own Id: OTP-11377

• Fix various typos in erts, kernel and ssh. Thanks to Martin Hässler.

  Own Id: OTP-11414

• Fix rpc multicall sample code. Thanks to Edwin Fine.

  Own Id: OTP-11471

• Under rare circumstances a process calling inet:close/1, gen_tcp:close/1, gen_udp:close/1, or gen_sctp:close/1 could hang in the call indefinitely.

  Own Id: OTP-11491

Improvements and New Features

• Add more SCTP errors as described in RFC 4960. Thanks to Artem Teslenko.

  Own Id: OTP-11379

• Add new BIF os:unsetenv/1 which deletes an environment variable. Thanks to Martin Hässler.

  Own Id: OTP-11446

1.52  Kernel 2.16.3

Fixed Bugs and Malfunctions

• Fix indentation of User switch command help in Erlang shell. Thanks to Sylvain Benner.

  Own Id: OTP-11209

Improvements and New Features

• The previous undocumented function ntoa/1 has been added to inet docs and exported in the inet module.

  Own Id: OTP-10676 Aux Id: OTP-10314

• Fix typo in abcast() function comment. Thanks to Johannes Weissl.

  Own Id: OTP-11219

• Add application:ensure_all_started/1-2. Thanks to Fred Hebert.

  Own Id: OTP-11250

• Make edlin understand a few important control keys. Thanks to Stefan Zegenhagen.

  Own Id: OTP-11251

• Cleanup of hipe_unified_loader, eliminating uses of is_subtype/2 in specs, change module-local void functions to return 'ok' instead of [] and made sure there are no dialyzer warnings with --Wunmatched_returns. Thanks to Kostis Sagonas.

  Own Id: OTP-11301

1.53  Kernel 2.16.2

Fixed Bugs and Malfunctions

• A bug in prim_inet has been corrected. If the port owner was killed at a bad time while closing the socket port the port could become orphaned hence causing port and socket leaking. Reported by Fred Herbert, Dmitry Belyaev and others.

  Own Id: OTP-10497 Aux Id: OTP-10562

• A few bugs regarding case sensitivity for hostname resolution while using e.g the internal lookup types 'file' and 'dns' has been corrected. When looking up hostnames ASCII letters a-z are to be regarded as the same as A-Z according to RFC 4343 "Domain Name System (DNS) Case Insensitivity Clarification", and this was not always the case.

  Own Id: OTP-10689 Aux Id: seq12227

Improvements and New Features

• Add application:ensure_started/1,2. It is equivavlent to application:start/1,2 except it returns ok for already started applications.

  Own Id: OTP-10910

• Optimize communication with file io server. Thanks to Anthony Ramine.

  Own Id: OTP-11040

• Erlang source files with non-ASCII characters are now encoded in UTF-8 (instead of latin1).

  Own Id: OTP-11041 Aux Id: OTP-10907

• Optimization of simultaneous inet_db operations on the same socket by using a lock free implementation.

  Impact on the characteristics of the system: Improved performance.

  Own Id: OTP-11074

• The high_msgq_watermark and low_msgq_watermark inet socket options introduced in OTP-R16A could only be set on TCP sockets. These options are now generic and can be set on all types of sockets.

  Own Id: OTP-11075 Aux Id: OTP-10336

• Fix deep list argument error under Windows in os:cmd/1. Thanks to Aleksandr Vinokurov .

  Own Id: OTP-11104

1.54  Kernel 2.16.1

Fixed Bugs and Malfunctions

• A bug that could cause a crash with wrong reason has been corrected in the application_controller module.

  Own Id: OTP-10754

• Fix code:is_module_native/1 that sometimes in R16A returned false for hipe compiled modules containing BIFs such as lists.

  Own Id: OTP-10870

• Respect {exit_on_close,false} option on tcp socket in non-passive mode when receiving fails (due to an ill-formed packet for example) by only doing a half close and still allow sending on the socket. (Thanks to Anthony Molinaro and Steve Vinoski for reporting the problem)

  Own Id: OTP-10879

Improvements and New Features

• Slightly nicer error message when node start fails due to duplicate name. Thanks to Magnus Henoch.

  Own Id: OTP-10797

• Miscellaneous updates due to Unicode support.

  Own Id: OTP-10820

• Add a new function code:get_mode() can be used to detect how the code servers behaves. Thanks to Vlad Dumitrescu

  Own Id: OTP-10823

• Fix type of error Reason on gen_tcp:send/2. Thanks to Sean Cribbs.

  Own Id: OTP-10839

• file:list_dir_all/1 and file:read_link_all/1 that can handle raw file names have been added. See the User Guide for STDLIB for information about raw file names.

  Own Id: OTP-10852

1.55  Kernel 2.16

Fixed Bugs and Malfunctions

• It is no longer possible to have {Mod,Vsn} in the 'modules' list in a .app file.

  This was earlier possible, although never documented in the .app file reference manual. It was however visible in the documentation of application:load/[1,2], where the same term as in a .app file can be used as the first argument.

  The possibility has been removed since the Vsn part was never used.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-10417

• The contract of erl_ddll:format_error/1 has been corrected. (Thanks to Joseph Wayne Norton.)

  Own Id: OTP-10473

• Change printout of application crash message on startup to formated strings (Thanks to Serge Aleynikov)

  Own Id: OTP-10620

• The type ascii_string() in the base64 module has been corrected. The type file:file_info() has been cleaned up. The type file:fd() has been made opaque in the documentation.

  Own Id: OTP-10624 Aux Id: kunagi-352 [263]

Improvements and New Features

• Inet exported functionality

  inet:parse_ipv4_address/1, inet:parse_ipv4strict_address/1, inet:parse_ipv6_address/1, inet:parse_ipv6strict_address/1, inet:parse_address/1 and inet:parse_strict_address is now exported from the inet module.

  Own Id: OTP-8067 Aux Id: kunagi-274 [185]

• A boolean socket option 'ipv6_v6only' for IPv6 sockets has been added. The default value of the option is OS dependent, so applications aiming to be portable should consider using {ipv6_v6only,true} when creating an inet6 listening/destination socket, and if necessary also create an inet socket on the same port for IPv4 traffic. See the documentation.

  Own Id: OTP-8928 Aux Id: kunagi-193 [104]

• Support for Unicode has been implemented.

  Own Id: OTP-10302

• The documentation for global:register_name/3 has been updated to mention that the use of {Module,Function} as the method argument (resolve function) is deprecated.

  Own Id: OTP-10419

• Fixed bug where sendfile on oracle solaris would return an error when a partial send was done.

  Own Id: OTP-10549

• The error_handler module will now call '$handle_undefined_function'/2 if an attempt is made to call a non-existing function in a module that exists. See the documentation for error_handler module for details.

  Own Id: OTP-10617 Aux Id: kunagi-340 [251]

• Where necessary a comment stating encoding has been added to Erlang files. The comment is meant to be removed in Erlang/OTP R17B when UTF-8 becomes the default encoding.

  Own Id: OTP-10630

• Do not return wrong terms unnecessarily. (Thanks to Kostis Sagonas.)

  Own Id: OTP-10662

• Some examples overflowing the width of PDF pages have been corrected.

  Own Id: OTP-10665

• Add file:allocate/3 operation

  This operation allows pre-allocation of space for files. It succeeds only on systems that support such operation. (Thanks to Filipe David Manana)

  Own Id: OTP-10680

• Add application:get_key/3. The new function provides a default value for a configuration parameter. Thanks to Serge Aleynikov.

  Own Id: OTP-10694

• Add search to Erlang shell's history. Thanks to Fred Herbert.

  Own Id: OTP-10739

1.56  Kernel 2.15.3

Fixed Bugs and Malfunctions

• Ensure 'erl_crash.dump' when asked for it. This will change erl_crash.dump behaviour.

  * Not setting ERL_CRASH_DUMP_SECONDS will now terminate beam immediately on a crash without writing a crash dump file.

  * Setting ERL_CRASH_DUMP_SECONDS to 0 will also terminate beam immediately on a crash without writing a crash dump file, i.e. same as not setting ERL_CRASH_DUMP_SECONDS environment variable.

  * Setting ERL_CRASH_DUMP_SECONDS to a negative value will let the beam wait indefinitely on the crash dump file being written.

  * Setting ERL_CRASH_DUMP_SECONDS to a positive value will let the beam wait that many seconds on the crash dump file being written.

  A positive value will set an alarm/timeout for restart both in beam and in heart if heart is running.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-10422 Aux Id: kunagi-250 [161]

1.57  Kernel 2.15.2

Fixed Bugs and Malfunctions

• Fixed issue where using controlling_process/2 with self() as the second argument caused the port to leak if self() crashes. (Thanks to Ricardo Catalinas Jiménez)

  Own Id: OTP-10094

• When sending large files using the file:sendfile fallback file:sendfile would crash. This is now fixed.

  Own Id: OTP-10098

• Fix rpc:call/5 for local calls with a finite Timeout (Thanks to Tomer Chachamu)

  Own Id: OTP-10149

• fix escript/primary archive reloading

  If the mtime of an escript/primary archive file changes after being added to the code path, correctly reload the archive and update the cache. (Thanks to Tuncer Ayaz)

  Own Id: OTP-10151

• Support added for home directories named with non-ASCII characters (codepoints above 127) on a system running in Unicode file mode (e.g. on MacOSX or Linux with startup arguments +fnu or +fna with the right LOCALE). Also environment variables with Unicode content are supported in applicable environments.

  Own Id: OTP-10160

• Allow mixed IPv4 and IPv6 addresses to sctp_bindx

  Also allow mixed address families to bind, since the first address on a multihomed sctp socket must be bound with bind, while the rest are to be bound using sctp_bindx. At least Linux supports adding address of mixing families. Make inet_set_faddress function available also when HAVE_SCTP is not defined, since we use it to find an address for bind to be able to mix ipv4 and ipv6 addresses. Thanks to Tomas Abrahamsson

  Own Id: OTP-10217

Improvements and New Features

• Document inet options: high_watermark, priority, linger and a some other options that previously was undocumented.

  Own Id: OTP-10053

• Remove bit8 option support from inet

  Own Id: OTP-10056

• The type of the disk log header has been corrected. (Thanks to Niclas Eklund.)

  Own Id: OTP-10131

1.58  Kernel 2.15.1

Fixed Bugs and Malfunctions

• Driver output has been corrected so output of large binaries (> 4 GiB) now does not silently fail or crash the emulator, but either outputs the binary or fails the call. This means that writing a binary > 4 Gib to file now works but on e.g 64-bit Windows (that has scatter/gather I/O buffer segment lengths of 32 bits) fails. The behaviour may change in the future to always write the binary, in parts if necessary.

  Own Id: OTP-9820 Aux Id: OTP-9795

• erts: minor fix for unnecessary condition erts: change SENDFILE_CHUNK_SIZE from signed to unsigned (Thanks to jovi zhang)

  Own Id: OTP-9872

• Two contracts in gen_sctp have been corrected.

  Own Id: OTP-9874

• If a process calls a module with an running on_load handler, the process is supposed to be suspended. But if the module with the on_load handler was loading used code:load_binary/3, the call would instead fail with an undef exception.

  Own Id: OTP-9875

• File name and error reason is now returned if creation of a cookie fails. (Thanks to Magnus Henoch)

  Own Id: OTP-9954

• Fix port leak in zlib when passing invalid data to compress,uncompress,zip,unzip,gzip,gunzip.

  Own Id: OTP-9981

• Various typographical errors corrected in documentation for the global, error_logger, etop, lists, ets and supervisor modules and in the c_portdriver and kernel_app documentation. (Thanks to Ricardo Catalinas Jiménez)

  Own Id: OTP-9987

• Fix returned error from gen_tcp:accept/1,2 when running out of ports.

  The {error, enfile} return value is badly misleading and confusing for this case, since the Posix ENFILE errno value has a well-defined meaning that has nothing to do with Erlang ports. The fix changes the return value to {error, system_limit}, which is consistent with e.g. various file(3) functions. inet:format_error/1 has also been updated to support system_limit in the same manner as file:format_error/1. (Thanks to Per Hedeland)

  Own Id: OTP-9990

• erts_debug:size/1 has been corrected to take sharing in the environment of funs into account. For funs it used to always give the same result as erts_debug:flat_size/1.

  Own Id: OTP-9991

• In some cases when the process doing file:sendfile crashes while sending the file the efile_drv code would not clean up after itself correctly. This has now been fixed.

  Own Id: OTP-9993

• On BSD based platforms file:sendfile would sometime go into an infinite loop when sending big files. This has now been fixed.

  Own Id: OTP-9994

• While disk_log eagerly collects logged terms for better performance, collecting too much data may choke the system and cause huge binaries to be written.

  The problem was addressed in OTP-9764, but the situation was not improved in all cases.

  (Thanks to Richard Carlsson.)

  Own Id: OTP-9999 Aux Id: OTP-9764

• The documentation of .app files incorrectly said that the default value for the mod parameter is undefined. This is now corrected to [].

  Own Id: OTP-10002

1.59  Kernel 2.15

Fixed Bugs and Malfunctions

• Calls to global:whereis_name/1 have been substituted for calls to global:safe_whereis_name/1 since the latter is not safe at all.

  The reason for not doing this earlier is that setting a global lock masked out a bug concerning the restart of supervised children. The bug has now been fixed by a modification of global:whereis_name/1. (Thanks to Ulf Wiger for code contribution.)

  A minor race conditions in gen_fsm:start* has been fixed: if one of these functions returned {error, Reason} or ignore, the name could still be registered (either locally or in global. (This is the same modification as was done for gen_server in OTP-7669.)

  The undocumented function global:safe_whereis_name/1 has been removed.

  Own Id: OTP-9212 Aux Id: seq7117, OTP-4174

• Honor option packet_size for http packet parsing by both TCP socket and erlang:decode_packet. This gives the ability to accept HTTP headers larger than the default setting, but also avoid DoS attacks by accepting lines only up to whatever length you wish to allow. For consistency, packet type line also honor option packet_size. (Thanks to Steve Vinoski)

  Own Id: OTP-9389

• disk_log:reopen/2,3 and disk_log:breopen/3 could return the error reason from file:rename/2 rather than the reason {file_error, Filename, Reason}. This bug has been fixed.

  The message {disk_log, Node, {error, disk_log_stopped}} which according the documentation is sent upon failure to truncate or reopen a disk log was sometimes turned into a reply. This bug has been fixed.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-9508

• Environment variable 'shutdown_timeout' is added to kernel application. Earlier, application_controller would hang forever if an application top supervisor did not terminate upon a shutdown request. If this new environment variable is set to a positive integer T, then application controller will now give up after T milliseconds and instead brutally kill the application. For backwards compatibility, the default value for shutdown_timeout is 'infinity'.

  Own Id: OTP-9540

• Add '-callback' attributes in stdlib's behaviours

  Replace the behaviour_info(callbacks) export in stdlib's behaviours with -callback' attributes for all the callbacks. Update the documentation with information on the callback attribute Automatically generate 'behaviour_info' function from '-callback' attributes

  'behaviour_info(callbacks)' is a special function that is defined in a module which describes a behaviour and returns a list of its callbacks.

  This function is now automatically generated using the '-callback' specs. An error is returned by lint if user defines both '-callback' attributes and the behaviour_info/1 function. If no type info is needed for a callback use a generic spec for it. Add '-callback' attribute to language syntax

  Behaviours may define specs for their callbacks using the familiar spec syntax, replacing the '-spec' keyword with '-callback'. Simple lint checks are performed to ensure that no callbacks are defined twice and all types referred are declared.

  These attributes can be then used by tools to provide documentation to the behaviour or find discrepancies in the callback definitions in the callback module.

  Add callback specs into 'application' module in kernel Add callback specs to tftp module following internet documentation Add callback specs to inets_service module following possibly deprecated comments

  Own Id: OTP-9621

• make tab completion work in remote shells (Thanks to Mats Cronqvist)

  Own Id: OTP-9673

• Add missing parenthesis in heart doc.

  Add missing spaces in the Reference Manual distributed section.

  In the HTML version of the doc those spaces are necessary to separate those words.

  Own Id: OTP-9693

• Fixes net_kernel:get_net_ticktime() doc

  Adds missing description when `ignored' is returned. (Thanks to Ricardo Catalinas Jiménez )

  Own Id: OTP-9713

• While disk_log eagerly collects logged terms for better performance, collecting too much data may choke the system and cause huge binaries to be written. In order to remedy the situation a (small) limit on the amount of data that is collected before writing to disk has been introduced.

  Own Id: OTP-9764

• • Correct callback spec in application module

  • Refine warning about callback specs with extra ranges

  • Cleanup autoimport compiler directives

  • Fix Dialyzer's warnings in typer

  • Fix Dialyzer's warning for its own code

  • Fix bug in Dialyzer's behaviours analysis

  • Fix crash in Dialyzer

  • Variable substitution was not generalizing any unknown variables.

  Own Id: OTP-9776

• Fix a crash when file:change_time/2,3 are called with invalid dates

  Calling file:change_time/2,3 with an invalid date tuple (e.g file:change_time("file.txt", {undefined, undefined})) will cause file_server_2 to crash. error_logger will shutdown and the whole VM will stop. Change behavior to validate given dates on system boundaries. (i.e before issuing a server call).(Thanks to Ahmed Omar)

  Own Id: OTP-9785

Improvements and New Features

• An option list argument can now be passed to file:read_file_info/2, file:read_link_info/2 and file:write_file_info/3 and set time type information in the call. Valid options are {time, local}, {time, universal} and {time, posix}. In the case of posix time no conversions are made which makes the operation a bit faster.

  Own Id: OTP-7687

• file:list_dir/1,2 will now fill an buffer entire with filenames from the efile driver before sending it to an erlang process. This will speed up this file operation in most cases.

  Own Id: OTP-9023

• gen_sctp:open/0-2 may now return {error,eprotonosupport} if SCTP is not supported

  gen_sctp:peeloff/1 has been implemented and creates a one-to-one socket which also are supported now

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-9239

• Sendfile has been added to the file module's API. sendfile/2 is used to read data from a file and send it to a tcp socket using a zero copying mechanism if available on that OS.

  Thanks to Tuncer Ayaz and Steve Vinovski for original implementation

  Own Id: OTP-9240

• Tuple funs (a two-element tuple with a module name and a function) are now officially deprecated and will be removed in R16. Use 'fun M:F/A' instead. To make you aware that your system uses tuple funs, the very first time a tuple fun is applied, a warning will be sent to the error logger.

  Own Id: OTP-9649

1.60  Kernel 2.14.5

Fixed Bugs and Malfunctions

• Fix type of Packet arg of gen_tcp:send/2 and gen_udp:send/4

  The type is marked as a binary() or a string() but in practice it can be an iodata(). The test suite was updated to confirm the gen_tcp/2 and gen_udp:send/4 functions accept iodata() (iolists) packets. (Thanks to Filipe David Manana)

  Own Id: OTP-9514

• XML files have been corrected.

  Own Id: OTP-9550 Aux Id: OTP-9541

Improvements and New Features

• The types and specifications of the inet modules have been improved.

  Own Id: OTP-9260

• Types and specifications have been added.

  Own Id: OTP-9356

• Contracts in STDLIB and Kernel have been improved and type errors have been corrected.

  Own Id: OTP-9485

• Update documentation and specifications of some of the zlib functions.

  Own Id: OTP-9506

1.61  Kernel 2.14.4

Fixed Bugs and Malfunctions

• The send_timeout option in gen_tcp did not work properly in active mode or with {active,once} options. This is now corrected.

  Own Id: OTP-9145

• Fixed various typos across the documentation (Thanks to Tuncer Ayaz)

  Own Id: OTP-9154

• Fix typo in doc of rpc:pmap/3 (Thanks to Ricardo Catalinas Jiménez)

  Own Id: OTP-9168

• A bug in inet_res, the specialized DNS resolver, has been corrected. A late answer with unfortunate timing could cause a runtime exception. Some code cleanup and improvements also tagged along. Thanks to Evegeniy Khramtsov for a pinpointing bug report and bug fix testing.

  Own Id: OTP-9221 Aux Id: OTP-8712

Improvements and New Features

• Types and specifications have been added.

  Own Id: OTP-9268

• Erlang types and specifications are used for documentation.

  Own Id: OTP-9272

• Two opaque types that could cause warnings when running Dialyzer have been modified.

  Own Id: OTP-9337

1.62  Kernel 2.14.3

Fixed Bugs and Malfunctions

• os:find_executable/{1,2} will no longer return the path of a directory that happens to be in the PATH.

  Own Id: OTP-8983 Aux Id: seq11749

• Fix -spec for file:write_file/3

  Change type for second parameter from binary() to iodata(), since the function explicitly takes steps to accept lists as well as binaries. (thanks to Magnus Henoch).

  Own Id: OTP-9067

• Sanitize the specs of the code module

  After the addition of unicode_binary() to the file:filename() type, dialyzer started complaining about erroneous or incomplete specs in some functions of the 'code' module. The culprit was hard-coded information in erl_bif_types for functions of this module, which were not updated. Since these functions have proper specs these days and code duplication (pun intended) is never a good idea, their type information was removed from erl_bif_types.

  While doing this, some erroneous comments were fixed in the code module and also made sure that the code now runs without dialyzer warnings even when the -Wunmatched_returns option is used.

  Some cleanups were applied to erl_bif_types too.

  Own Id: OTP-9100

• - Add spec for function that does not return - Strenghen spec - Introduce types to avoid duplication in specs - Add specs for functions that do not return - Add specs for behaviour callbacks - Simplify two specs

  Own Id: OTP-9127

1.63  Kernel 2.14.2

Improvements and New Features

• The Erlang VM now supports Unicode filenames. The feature is turned on by default on systems where Unicode filenames are mandatory (Windows and MacOSX), but can be enabled on other systems with the '+fnu' emulator option. Enabling the Unicode filename feature on systems where it is not default is however considered experimental and not to be used for production. Together with the Unicode file name support, the concept of "raw filenames" is introduced, which means filenames provided without implicit unicode encoding translation. Raw filenames are provided as binaries, not lists. For further information, see stdlib users guide and the chapter about using Unicode in Erlang. Also see the file module manual page.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-8887

• There is now a new function inet:getifaddrs/0 modeled after C library function getifaddrs() on BSD and LInux that reports existing interfaces and their addresses on the host. This replaces the undocumented and unsupported inet:getiflist/0 and inet:ifget/2.

  Own Id: OTP-8926

1.64  Kernel 2.14.1.1

Fixed Bugs and Malfunctions

• In embedded mode, on_load handlers that called code:priv_dir/1 or other functions in code would hang the system. Since the crypto application now contains an on_loader handler that calls code:priv_dir/1, including the crypto application in the boot file would prevent the system from starting.

  Also extended the -init_debug option to print information about on_load handlers being run to facilitate debugging.

  Own Id: OTP-8902 Aux Id: seq11703

1.65  Kernel 2.14.1

Fixed Bugs and Malfunctions

• Fixed: inet:setopts(S, [{linger,{true,2}}]) returned {error,einval} for SCTP sockets. The inet_drv had a bug when checking the option size.

  Own Id: OTP-8726 Aux Id: seq11617

• gen_udp:connect/3 was broken for SCTP enabled builds. It did not detect remote end errors as it should.

  Own Id: OTP-8729

• reference() has been substituted for ref() in the documentation.

  Own Id: OTP-8733

• A bug introduced in kernel-2.13.5.3 has been fixed. If running net_kernel:set_net_ticktime/1 twice within the TransitionPerod the second call caused the net_kernel process to crash with a badmatch.

  Own Id: OTP-8787 Aux Id: seq11657, OTP-8643

• inet:getsockopt for SCTP sctp_default_send_param had a bug to not initialize required feilds causing random answers. It is now corrected.

  Own Id: OTP-8795 Aux Id: seq11655

• For a socket in the HTTP packet mode, the return value from gen_tcp:recv/2,3 if there is an error in the header will be {ok,{http_error,String}} instead of {error,{http_error,String}} to be consistent with ssl:recv/2,3.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-8831

Improvements and New Features

• Even when configuring erlang with --enable-native-libs, the native code for modules loaded very early (such as lists) would not get loaded. This has been corrected. (Thanks to Paul Guyot.)

  Own Id: OTP-8750

• The undocumented function inet:ifget/2 has been improved to return interface hardware address (MAC) on platforms supporting getaddrinfo() (such as BSD unixes). Note it still does not work on all platforms for example not Windows nor Solaris, so the function is still undocumented.

  Buffer overflow and field init bugs for inet:ifget/2 and inet:getservbyname/2 has also been fixed.

  Thanks to Michael Santos.

  Own Id: OTP-8816

• As a usability improvement the 'inet6' option to functions gen_tcp:listen/2, gen_tcp:connect/3-4, gen_udp:open/2 and gen_sctp:open/1-2 is now implicit if the address argument or the 'ip' option contain an IPv6 address (8-tuple).

  Own Id: OTP-8822

1.66  Kernel 2.14

Fixed Bugs and Malfunctions

• os:find_executable can now be fed with the complete name of the executable on Windows and still find it. I.e os:find_executable("werl.exe") will work as os:find_executable("werl").

  Own Id: OTP-3626

• The shell's line editing has been improved to more resemble the behaviour of readline and other shells. (Thanks to Dave Peticolas)

  Own Id: OTP-8635

• Under certain circumstances the net kernel could hang. (Thanks to Scott Lystig Fritchie.)

  Own Id: OTP-8643 Aux Id: seq11584

• The kernel DNS resolver was leaking one or two ports if the DNS reply could not be parsed or if the resolver(s) caused noconnection type errors. Bug now fixed. A DNS specification borderline truncated reply triggering the port leakage bug has also been fixed.

  Own Id: OTP-8652

Improvements and New Features

• As of this version, the global name server no longer supports nodes running Erlang/OTP R11B.

  Own Id: OTP-8527

• The file module's functions write,read and read_line now handles named io_servers like 'standard_io' and 'standard_error' correctly.

  Own Id: OTP-8611

• The functions file:advise/4 and file:datasync/1 have been added. (Thanks to Filipe David Manana.)

  Own Id: OTP-8637

• When exchanging groups between nodes pg2 did not remove duplicated members. This bug was introduced in R13B03 (kernel-2.13.4).

  Own Id: OTP-8653

• There is a new option 'exclusive' to file:open/2 that uses the OS O_EXCL flag where supported to open the file in exclusive mode.

  Own Id: OTP-8670

1.67  Kernel 2.13.5.3

Fixed Bugs and Malfunctions

• A bug introduced in Kernel 2.13.5.2 has been fixed.

  Own Id: OTP-8686 Aux Id: OTP-8643

1.68  Kernel 2.13.5.2

Fixed Bugs and Malfunctions

• Under certain circumstances the net kernel could hang. (Thanks to Scott Lystig Fritchie.)

  Own Id: OTP-8643 Aux Id: seq11584

1.69  Kernel 2.13.5.1

Fixed Bugs and Malfunctions

• A race condition in os:cmd/1 could cause the caller to get stuck in os:cmd/1 forever.

  Own Id: OTP-8502

1.70  Kernel 2.13.5

Fixed Bugs and Malfunctions

• A race bug affecting pg2:get_local_members/1 has been fixed. The bug was introduced in R13B03.

  Own Id: OTP-8358

• The loading of native code was not properly atomic in the SMP emulator, which could cause crashes. Also a per-MFA information table for the native code has now been protected with a lock since it turns that it could be accessed concurrently in the SMP emulator. (Thanks to Mikael Pettersson.)

  Own Id: OTP-8397

• user.erl (used in oldshell) is updated to handle unicode in prompt strings (io:get_line/{1,2}). io_lib is also updated to format prompts with the 't' modifier (i.e. ~ts instead of ~s).

  Own Id: OTP-8418 Aux Id: OTP-8393

• The resolver routines failed to look up the own node name as hostname, if the OS native resolver was erroneously configured, bug reported by Yogish Baliga, now fixed.

  The resolver routines now tries to parse the hostname as an IP string as most OS resolvers do, unless the native resolver is used.

  The DNS resolver inet_res and file resolver inet_hosts now do not read OS configuration files until they are needed. Since the native resolver is default, in most cases they are never needed.

  The DNS resolver's automatic updating of OS configuration file data (/etc/resolv.conf) now uses the 'domain' keyword as default search domain if there is no 'search' keyword.

  Own Id: OTP-8426 Aux Id: OTP-8381

Improvements and New Features

• The expected return value for an on_load function has been changed. (See the section about code loading in the Reference manual.)

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-8339

• Explicit top directories in archive files are now optional.

  For example, if an archive (app-vsn.ez) just contains an app-vsn/ebin/mod.beam file, the file info for the app-vsn and app-vsn/ebin directories are faked using the file info from the archive file as origin. The virtual direcories can also be listed. For short, the top directories are virtual if they does not exist.

  Own Id: OTP-8387

• code:clash/0 now looks inside archives (.ez files). (Thanks to Tuncer Ayaz.)

  Own Id: OTP-8413

• There are new gen_sctp:connect_init/* functions that initiate an SCTP connection without blocking for the result. The result is delivered asynchronously as an sctp_assoc_change event. (Thanks to Simon Cornish.)

  Own Id: OTP-8414

1.71  Kernel 2.13.4

Fixed Bugs and Malfunctions

• A link in pg2(3) has been fixed. (Thanks to Christophe Romain.)

  Own Id: OTP-8198

• A ticker process could potentially be blocked indefinitely trying to send a tick to a node not responding. If this happened, the connection would not be brought down as it should.

  Own Id: OTP-8218

• A bug in pg2 when members who died did not leave process groups has been fixed. (Thanks to Matthew Dempsky.)

  Own Id: OTP-8259

Improvements and New Features

• The documentation is now built with open source tools (xsltproc and fop) that exists on most platforms. One visible change is that the frames are removed.

  Own Id: OTP-8201

• The top directory in archive files does not need to have a -vsn suffix anymore. For example if the archive file has the name like mnesia-4.4.7.ez the top directory in the archive can either be named mnesia or mnesia-4.4.7. If the archive file has a name like mnesia.ez the top directory in the archive must be named mnesia as earlier.

  Own Id: OTP-8266

• The -on_load() directive can be used to run a function when a module is loaded. It is documented in the section about code loading in the Reference Manual.

  Own Id: OTP-8295

1.72  Kernel 2.13.3

Improvements and New Features

• The DNS resolver client inet_res has been rewritten, documented and released. See inet_res(3) and Erts User's Guide: Inet configuration.

  It can formally not be incompatible with respect to earlier versions since there was no earlier official version. However it was used before and some details have changed.

  Configuration now initializes from /etc/resolv.conf and /etc/hosts on all unix platforms regardless of which distribution mode the node is started in. The directory (/etc) these files are supposed to reside in can be changed via an environment variable. These configuration file locations can also be changed in the inet configuration. The files are monitored for change and re-read, which makes a few resolver configuration variables out of application control. The /etc/hosts entries have now their own cache table that is shadowed (with lookup method 'file' is used) by the application configured host entries. This problem (that inet_res configuration only worked for distribution mode long names) was among other reported by Matthew O'Gorman many moons ago.

  The lookup methods are still 'native' only per default. Resolver configuration is done on all Unix platforms just to get a usable configuration for direct calls to inet_res.

  The functions inet_res:nslookup/3..5 and inet_res:nnslookup/4..4 are no longer recommended to use, instead use inet_res:lookup/3..5 and inet_res:resolve/3..5 which provide clearer argument types and the possibility to override options in the call.

  Users of previous unsupported versions of inet_res have included internal header files to get to the internal record definitions in order to examine DNS replies. This is still unsupported and there are access functions in inet_dns to use instead. These are documented in inet_res(3).

  Bug fix: a compression reference loop would make DNS message decoding loop forever. Problem reported by Florian Weimer.

  Bug fix and patch suggestion by Sergei Golovan: configuring IPv6 nameservers did not work. His patch (as he warned) created many UDP sockets; one per nameserver. This has been fixed in the released version.

  Improvement: inet_res is now EDNS0 capable. The current implementation is simple and does not probe and cache EDNS info for nameservers, which a fully capable implementation probably should do. EDNS has to be enabled via resolver configuration, and if a nameserver replies that it does not support EDNS, inet_res falls back to a regular DNS query.

  Improvement: now inet_res automatically falls back to TCP if it gets a truncated answer from a nameserver.

  Warning: some of the ancient and exotic record types handled by inet_res and inet_dns are not supported by current versions of BIND, so they could not be tested after the rewrite, with reasonable effort, e.g MD, MF, NULL, and SPF. The risk for bugs in these particular records is still low since their code is mostly shared with other tested record types.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-7955 Aux Id: OTP-7107 OTP-6852

• A TCP socket with option {packet,4} could crash the emulator if it received a packet header with a very large size value (>2Gb). The same bug caused erlang:decode_packet/3 to return faulty values. (Thanks to Georgos Seganos.)

  Own Id: OTP-8102

• The file module has now a read_line/1 function similar to the io:get_line/2, but with byte oriented semantics. The function file:read_line/1 works for raw files as well, but for good performance it is recommended to use it together with the 'read_ahead' option for raw file access.

  Own Id: OTP-8108

1.73  Kernel 2.13.2

Fixed Bugs and Malfunctions

• A bug when doing io:get_line (among other calls) from a file opened with encoding other than latin1, causing false unicode errors to occur, is now corrected.

  Own Id: OTP-7974

Improvements and New Features

• Added functionality to get higher resolution timestamp from system. The erlang:now function returns a timestamp that's not always consistent with the actual operating system time (due to resilience against large time changes in the operating system). The function os:timestamp/0 is added to get a similar timestamp as the one being returned by erlang:now, but untouched by Erlangs time correcting and smoothing algorithms. The timestamp returned by os:timestamp is always consistent with the operating systems view of time, like the calendar functions for getting wall clock time, but with higher resolution. Example of usage can be found in the os manual page.

  Own Id: OTP-7971

1.74  Kernel 2.13.1

Fixed Bugs and Malfunctions

• Many concurrent calls to os:cmd/1 will only block one scheduler thread at a time, making an smp emulator more responsive if the OS is slow forking processes.

  Own Id: OTP-7890 Aux Id: seq11219

• Fixed hanging early RPC that did IO operation during node start.

  Own Id: OTP-7903 Aux Id: seq11224

• The error behavior of gen_tcp and gen_udp has been corrected. gen_tcp:connect/3,4 and gen_udp:send/4 now returns {error,eafnosupport} for conflicting destination address versus socket address family. Other corner cases for IP address string host names combined with not using the native (OS) resolver (which is not default) has also been changed to return {error,nxdomain} instead of {error,einval}. Those changes just may surprise old existing code. gen_tcp:listen/2 and gen_udp:open/2 now fails for conflicting local address versus socket address family instead of trying to use an erroneous address. Problem reported by Per Hedeland.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-7929

Improvements and New Features

• Several glitches and performance issues in the Unicode and I/O-system implementation of R13A have been corrected.

  Own Id: OTP-7896 Aux Id: OTP-7648 OTP-7887

• The unsupported DNS resolver client inet_res has now been improved to handle NAPTR queries.

  Own Id: OTP-7925 Aux Id: seq11231

1.75  Kernel 2.13

Fixed Bugs and Malfunctions

• The old Erlang DNS resolver inet_res has been corrected to handle TXT records with more than one character string. Patch courtesy of Geoff Cant.

  Own Id: OTP-7588

• When chunk reading a disk log opened in read_only mode, bad terms could crash the disk log process.

  Own Id: OTP-7641 Aux Id: seq11090

• gen_tcp:send() did sometimes (only observed on Solaris) return {error,enotconn} instead of the expected {error,closed} as the peer socket had been explicitly closed.

  Own Id: OTP-7647

• The gen_sctp option sctp_peer_addr_params, #sctp_paddrparams{address={IP,Port} was erroneously decoded in the inet driver. This bug has now been corrected.

  Own Id: OTP-7755

Improvements and New Features

• Erlang programs can now access STDERR on platforms where such a file descriptor is available by using the io_server 'standard_error', i.e. io:format(standard_error,"~s~n",[ErrorMessage]),

  Own Id: OTP-6688

• The format of the string returned by erlang:system_info(system_version) (as well as the first message when Erlang is started) has changed. The string now contains the both the OTP version number as well as the erts version number.

  Own Id: OTP-7649

• As of this version, the global name server no longer supports nodes running Erlang/OTP R10B.

  Own Id: OTP-7661

• A {nodedown, Node} message passed by the net_kernel:monitor_nodes/X functionality is now guaranteed to be sent after Node has been removed from the result returned by erlang:nodes/Y.

  Own Id: OTP-7725

• The deprecated functions erlang:fault/1, erlang:fault/2, and file:rawopen/2 have been removed.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-7812

• Nodes belonging to different independent clusters can now co-exist on the same host with the help of a new environment variable setting ERL_EPMD_PORT.

  Own Id: OTP-7826

• The copyright notices have been updated.

  Own Id: OTP-7851

1.76  Kernel 2.12.5.1

Fixed Bugs and Malfunctions

• When chunk reading a disk log opened in read_only mode, bad terms could crash the disk log process.

  Own Id: OTP-7641 Aux Id: seq11090

• Calling gen_tcp:send() from several processes on socket with option send_timeout could lead to much longer timeout than specified. The solution is a new socket option {send_timeout_close,true} that will do automatic close on timeout. Subsequent calls to send will then immediately fail due to the closed connection.

  Own Id: OTP-7731 Aux Id: seq11161

1.77  Kernel 2.12.5

Fixed Bugs and Malfunctions

• The documentation of rpc:pmap/3 has been corrected. (Thanks to Kirill Zaborski.)

  Own Id: OTP-7537

• The listen socket used for the distributed Erlang protocol now uses the socket option 'reuseaddr', which is useful when you force the listen port number using kernel options 'inet_dist_listen_min' and 'inet_dist_listen_max' and restarts a node with open connections.

  Own Id: OTP-7563

• Fixed memory leak of unclosed TCP-ports. A gen_tcp:send() followed by a failing gen_tcp:recv() could in some cases cause the port to linger after being closed.

  Own Id: OTP-7615

Improvements and New Features

• Processes spawned using proc_lib (including gen_server and other library modules that use proc_lib) no longer keep the entire argument list for the initial call, but only the arity.

  Also, if proc_lib:spawn/1 is used to spawn a fun, the actual fun is not kept, but only module, function name, and arity of the function that implements the fun.

  The reason for the change is that keeping the initial fun (or a fun in an argument list), would prevent upgrading the code for the module. A secondary reason is that keeping the fun and function arguments could waste a significant amount of memory.

  The drawback with the change is that the crash reports will provide less precise information about the initial call (only Module:Function/Arity instead of Module:Function(Arguments)). The function proc_lib:initial_call/1 still returns a list, but each argument has been replaced with a dummy atom.

  Own Id: OTP-7531 Aux Id: seq11036

• io:get_line/1 when reading from standard input is now substantially faster. There are also some minor performance improvements in io:get_line/1 when reading from any file opened in binary mode. (Thanks to Fredrik Svahn.)

  Own Id: OTP-7542

• There is now experimental support for loading of code from archive files. See the documentation of code, init, erl_prim_loader and escript for more info.

  The error handling of escripts has been improved.

  An escript may now set explicit arguments to the emulator, such as -smp enabled.

  An escript may now contain a precompiled beam file.

  An escript may now contain an archive file containing one or more applications (experimental).

  The internal module code_aux has been removed.

  Own Id: OTP-7548 Aux Id: otp-6622

• code:is_sticky/1 is now documented. (Thanks to Vlad Dumitrescu.)

  Own Id: OTP-7561

• In the job control mode, the "s" and "r" commands now take an optional argument to specify which shell to start. (Thanks to Robert Virding.)

  Own Id: OTP-7617

• net_adm:world/0,1 could crash if called in an emulator that has not been started with either the -sname or -name option; now it will return an empty list. (Thanks to Edwin Fine.)

  Own Id: OTP-7618

1.78  Kernel 2.12.4

Fixed Bugs and Malfunctions

• Large files are now handled on Windows, where the filesystem supports it.

  Own Id: OTP-7410

Improvements and New Features

• New BIF erlang:decode_packet/3 that extracts a protocol packet from a binary. Similar to the socket option {packet, Type}. Also documented the socket packet type http and made it official. NOTE: The tuple format for http packets sent from an active socket has been changed in an incompatible way.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-7404

• Setting the {active,once} for a socket (using inets:setopts/2) is now specially optimized (because the {active,once} option is typically used much more frequently than other options).

  Own Id: OTP-7520

1.79  Kernel 2.12.3

Fixed Bugs and Malfunctions

• SCTP_ADDR_CONFIRMED events are now handled by gen_sctp.

  Own Id: OTP-7276

• When leaving a process group with pg2:leave/2 the process was falsely assumed to be a member of the group. This bug has been fixed.

  Own Id: OTP-7277

• In the Erlang shell, using up and down arrow keys, the wrong previous command could sometimes be retrieved.

  Own Id: OTP-7278

• The documentation for erlang:trace/3 has been corrected.

  Own Id: OTP-7279 Aux Id: seq10927

• In the SMP emulator, there was small risk that code:purge(Mod) would kill a process that was running code in Mod and unload the module Mod before the process had terminated. code:purge(Mod) now waits for confirmation (using erlang:monitor/2) that the process has been killed before proceeding.

  Own Id: OTP-7282

• zlib:inflate failed when the size of the inflated data was an exact multiple of the internal buffer size (4000 bytes by default).

  Own Id: OTP-7359

Improvements and New Features

• Additional library directories can now be specified in the environment variable ERL_LIBS. See the manual page for the code module. (Thanks to Serge Aleynikov.)

  Own Id: OTP-6940

• crypto and zlib drivers improved to allow concurrent smp access.

  Own Id: OTP-7262

• There is a new function init:stop/1 which can be used to shutdown the system cleanly AND generate a non-zero exit status or crash dump. (Thanks to Magnus Froberg.)

  Own Id: OTP-7308

• The hide option for open_port/2 is now documented. (Thanks to Richard Carlsson.)

  Own Id: OTP-7358

1.80  Kernel 2.12.2.1

Improvements and New Features

• os:cmd/1 on unix platforms now use /bin/sh as shell instead of looking for sh in the PATH environment.

  Own Id: OTP-7283

1.81  Kernel 2.12.2

Fixed Bugs and Malfunctions

• A bug caused by a race condition involving disk_log and pg2 has been fixed.

  Own Id: OTP-7209 Aux Id: seq10890

• The beta testing module gen_sctp now supports active mode as stated in the documentation. Active mode is still rather untested, and there are some issues about what should be the right semantics for gen_sctp:connect/5. In particular: should it be blocking or non-blocking or choosable. There is a high probability it will change semantics in a (near) future patch.

  Try it, give comments and send in bug reports!

  Own Id: OTP-7225

Improvements and New Features

• erlang:system_info/1 now accepts the logical_processors, and debug_compiled arguments. For more info see the, erlang(3) documentation.

  The scale factor returned by test_server:timetrap_scale_factor/0 is now also effected if the emulator uses a larger amount of scheduler threads than the amount of logical processors on the system.

  Own Id: OTP-7175

• Updated the documentation for erlang:function_exported/3 and io:format/2 functions to no longer state that those functions are kept mainly for backwards compatibility.

  Own Id: OTP-7186

• A process executing the processes/0 BIF can now be preempted by other processes during its execution. This in order to disturb the rest of the system as little as possible. The returned result is, of course, still a consistent snapshot of existing processes at a time during the call to processes/0.

  The documentation of the processes/0 BIF and the is_process_alive/1 BIF have been updated in order to clarify the difference between an existing process and a process that is alive.

  Own Id: OTP-7213

• tuple_size/1 and byte_size/1 have been substituted for size/1 in the documentation.

  Own Id: OTP-7244

1.82  Kernel 2.12.1.2

Improvements and New Features

• The {allocator_sizes, Alloc} and alloc_util_allocators arguments are now accepted by erlang:system_info/1. For more information see the erlang(3) documentation.

  Own Id: OTP-7167

1.83  Kernel 2.12.1.1

Fixed Bugs and Malfunctions

• Fixed a problem in group that could cause the ssh server to lose answers or hang.

  Own Id: OTP-7185 Aux Id: seq10871

1.84  Kernel 2.12.1

Fixed Bugs and Malfunctions

• file:read/2 and file:consult_stream/1,3 did not use an empty prompt on I/O devices. This bug has now been corrected.

  Own Id: OTP-7013

• The sctp driver has been updated to work against newer lksctp packages e.g 1.0.7 that uses the API spelling change adaption -> adaptation. Older lksctp (1.0.6) still work. The erlang API in gen_sctp.erl and inet_sctp.hrl now spells 'adaptation' regardless of the underlying C API.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-7120

Improvements and New Features

• The documentation has been updated so as to reflect the last updates of the Erlang shell as well as the minor modifications of the control sequence p of the io_lib module.

  Superfluous empty lines have been removed from code examples and from Erlang shell examples.

  Own Id: OTP-6944 Aux Id: OTP-6554, OTP-6911

• tuple_size/1 and byte_size/1 have been substituted for size/1.

  Own Id: OTP-7009

1.85  Kernel 2.12

Fixed Bugs and Malfunctions

• A bug for raw files when reading 0 bytes returning 'eof' instead of empty data has been corrected.

  Own Id: OTP-6291 Aux Id: OTP-6967

• A bug in gen_udp:fdopen reported by David Baird and also found by Dialyzer has been fixed.

  Own Id: OTP-6836 Aux Id: OTP-6594

• Calling error_logger:tty(true) multiple times does not give multiple error log printouts.

  Own Id: OTP-6884 Aux Id: seq10767

• The global name server now ignores nodeup messages when the command line flag -connect_all false has been used. (Thanks to Trevor Woollacott.)

  Own Id: OTP-6931

• file:write_file/3, file:write/2 and file:read/2 could crash (contrary to documentation) for odd enough file system problems, e.g write to full file system. This bug has now been corrected.

  In this process the file module has been rewritten to produce better error codes. Posix error codes now originate from the OS file system calls or are generated only for very similar causes (for example 'enomem' is generated if a memory allocation fails, and 'einval' is generated if the file handle in Erlang is a file handle but currently invalid).

  More Erlang-ish error codes are now generated. For example {error,badarg} is now returned from file:close/1 if the argument is not of a file handle type. See file(3).

  The possibility to write a single byte using file:write/2 instead of a list or binary of one byte, contradictory to the documentation, has been removed.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-6967 Aux Id: OTP-6597 OTP-6291

• Monitor messages produced by the system monitor functionality, and garbage collect trace messages could contain erroneous heap and/or stack sizes when the actual heaps and/or stacks were huge.

  As of erts version 5.6 the large_heap option to erlang:system_monitor/[1,2] has been modified. The monitor message is sent if the sum of the sizes of all memory blocks allocated for all heap generations is equal to or larger than the specified size. Previously the monitor message was sent if the memory block allocated for the youngest generation was equal to or larger than the specified size.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-6974 Aux Id: seq10796

• inet:getopts/2 returned random values on Windows Vista.

  Own Id: OTP-7003

Improvements and New Features

• Minor documentation corrections for file:pread/2 and file:pread/3.

  Own Id: OTP-6853

• The deprecated functions file:file_info/1, init:get_flag/1, init:get_flags/0, and init:get_args/0 have been removed.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-6886

• Contract directives for modules in Kernel and STDLIB.

  Own Id: OTP-6895

• The functions io:columns/0, io:columns/1, io:rows/0 and io:rows/1 are added to allow the user to get information about the terminal geometry. The shell takes some advantage of this when formatting output. For regular files and other io-devices where height and width are not applicable, the functions return {error,enotsup}.

  Potential incompatibility: If one has written a custom io-handler, the handler has to either return an error or take care of io-requests regarding terminal height and width. Usually that is no problem as io-handlers, as a rule of thumb, should give an error reply when receiving unknown io-requests, instead of crashing.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-6933

• The undocumented and unsupported functions inet:ip_to_bytes/1, inet:ip4_to_bytes/1, inet:ip6_to_bytes/1, and inet:bytes_to_ip6/16 have been removed.

  Own Id: OTP-6938

• Added new checksum combine functions to zlib. And fixed a bug in zlib:deflate. Thanks Matthew Dempsky.

  Own Id: OTP-6970

• The spawn_monitor/1 and spawn_monitor/3 BIFs are now auto-imported (i.e. they no longer need an erlang: prefix).

  Own Id: OTP-6975

• All functions in the code module now fail with an exception if they are called with obviously bad arguments, such as a tuple when an atom was expected. Some functions now also fail for undocumented argument types (for instance, ensure_loaded/1 now only accepts an atom as documented; it used to accept a string too).

  Dialyzer will generally emit warnings for any calls that use undocumented argument types. Even if the call happens to still work in R12B, you should correct your code. A future release will adhere to the documentation.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-6983

1.86  Kernel 2.11.5.2

Fixed Bugs and Malfunctions

• The kernel parameter dist_auto_connect once could fail to block a node if massive parallel sends were issued during a transient failure of network communication

  Own Id: OTP-6893 Aux Id: seq10753

1.87  Kernel 2.11.5.1

Fixed Bugs and Malfunctions

• The internal (rarely used) DNS resolver has been modified to not use the domain search list when asked to resolve an absolute name; a name with a terminating dot. There was also a bug causing it to create malformed DNS queries for absolute names that has been corrected, correction suggested by Scott Lystig Fritchie. The code has also been corrected to look up cached RRs in the same search order as non-cached, now allows having the root domain among the search domains, and can now actually do a zone transfer request.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-6806 Aux Id: seq10714 EABln35459

• zlib:close/1 would leave an EXIT message in the message queue if the calling process had the trap_exit flag enabled.

  Own Id: OTP-6811

Improvements and New Features

• The documentation of process_flag(priority, Level) has been updated, see the erlang(3) documentation.

  Own Id: OTP-6745 Aux Id: OTP-6715

1.88  Kernel 2.11.5

Fixed Bugs and Malfunctions

• The shell has been updated to fix the following flaws: Shell process exit left you with an unresponsive initial shell if not using oldshell. Starting a restricted shell with a nonexisting callback module resulted in a shell where no commands could be used, not even init:stop/0. Fun's could not be used as parameters to local shell functions (in shell_default or user_default) when restricted_shell was active.

  Own Id: OTP-6537

• The undocumented feature gen_tcp:fdopen/2 was broken in R11B-4. It is now fixed again.

  Own Id: OTP-6615

• Corrected cancellation of timers in three places in the inet_res module. (Problem found by Dialyzer.)

  Own Id: OTP-6676

Improvements and New Features

• Corrected protocol layer flue for socket options SO_LINGER, SO_SNDBUF and SO_RCVBUF, for SCTP.

  Own Id: OTP-6625 Aux Id: OTP-6336

• The behaviour of the inet option {active,once} on peer close is improved and documented.

  Own Id: OTP-6681

• The inet option send_timeout for connection oriented sockets is added to allow for timeouts in communicating send requests to the underlying TCP stack.

  Own Id: OTP-6684 Aux Id: seq10637 OTP-6681

• Minor Makefile changes.

  Own Id: OTP-6689 Aux Id: OTP-6742

• The documentation of process_flag(priority, Level) has been updated, see the erlang(3) documentation.

  Own Id: OTP-6715

1.89  Kernel 2.11.4.2

Improvements and New Features

• process_flag/2 accepts the new flag sensitive.

  Own Id: OTP-6592 Aux Id: seq10555

1.90  Kernel 2.11.4.1

Fixed Bugs and Malfunctions

• A bug in gen_udp:open that broke the 'fd' option has been fixed.

  Own Id: OTP-6594 Aux Id: seq10619

1.91  Kernel 2.11.4

Fixed Bugs and Malfunctions

• Added a warning to the documentation for the error_logger functions error_msg/1,2, warning_msg/1,2 and info_msg/1,2 that calling these function with bad arguments can crash the standard event handler.

  Own Id: OTP-4575 Aux Id: seq7693

• A bug in inet_db concerning getting the resolver option retry has been corrected.

  Own Id: OTP-6380 Aux Id: seq10534

• Names registered by calling global:register_name() or global:re_register_name() were not always unregistered when the registering or registered process died. This bug has been fixed.

  Own Id: OTP-6428

• When setting the kernel configuration parameter error_logger to false, the documentation stated that "No error logger handler is installed". This is true, but error logging is not turned off, as the initial, primitive error logger event handler is kept, printing raw event messages to tty.

  Changing this behavior can be viewed as a backward incompatible change. Instead a new value silent for the configuration parameter has been added, which ensures that error logging is completely turned off.

  Own Id: OTP-6445

• Clarified the documentation for code:lib_dir/1 and code:priv_dir/1. The functions traverse the names of the code path, they do not search the actual directories.

  Own Id: OTP-6466

• io:setopts returned {error,badarg}, when called with only an expand_fun argument. (Thanks to igwan.)

  Own Id: OTP-6508

Improvements and New Features

• An interface towards the SCTP Socket API Extensions has been implemented.It is an Open Source patch courtesy of Serge Aleynikov and Leonid Timochouk. The Erlang code parts has been adapted by the OTP team, changing the Erlang API somewhat.

  The Erlang interface consists of the module gen_sctp and an include file -include_lib("kernel/include/inet_sctp.hrl"). for option record definitions. The gen_sctp module is documented.

  The delivered Open Source patch, before the OTP team rewrites, was written according to http://tools.ietf.org/html/draft-ietf-tsvwg-sctpsocket-13 and was claimed to work fine, tested on Linux Fedora Core 5.0 (kernel 2.6.15-2054 or later) and on Solaris 10 and 11. The OTP team rewrites used the same standard document but might have accidentally broken some functionality. If so, it will soon be patched to working state. The tricky parts in C and the general design has essentially not changed. During the rewrites the code was hand tested on SuSE Linux Enterprise Server 10, and briefly on Solaris 10. Feedbach on code and docs is very much appreciated.

  The SCTP interface is in beta state. It has only been hand tested and has no automatic test suites in OTP meaning everything is most certainly not tested. Socket active mode is broken. IPv6 is not tested. The documentation has been reworked due to the API changes, but has not been proofread after this.

  Thank you from the OTP team to Serge Aleynikov and Leonid Timochouk for a valuable contribution. We hope we have not messed it up too much.

  Own Id: OTP-6336

• A {minor_version,Version} option is now recognized by term_to_binary/2. {minor_version,1} will cause floats to be encoded in an exact and more space-efficient way compared to the previous encoding.

  Own Id: OTP-6434

• Monitoring of nodes has been improved. Now the following properties apply to net_kernel:monitor_nodes/[1,2]:

  • nodeup messages will be delivered before delivery of any message from the remote node passed through the newly established connection.
  • nodedown messages will not be delivered until all messages from the remote node that have been passed through the connection have been delivered.
  • Subscriptions can also be made before the net_kernel server has been started.

  Own Id: OTP-6481

• Setting and getting socket options in a "raw" fashion is now allowed. Using this feature will inevitably produce non portable code, but will allow setting ang getting arbitrary uncommon options on TCP stacks that do have them.

  Own Id: OTP-6519

• Dialyzer warnings have been eliminated.

  Own Id: OTP-6523

• The documentation for file:delete/1 and file:set_cwd/1 has been updated to clarify what happens if the input arguments are of an incorrect type.

  Own Id: OTP-6535

1.92  Kernel 2.11.3.1

Fixed Bugs and Malfunctions

• An erroneous packet size could be used for the first messages passed through a newly established connection between two Erlang nodes. This could cause messages to be discarded, or termination of the connection.

  Own Id: OTP-6473

1.93  Kernel 2.11.3

Fixed Bugs and Malfunctions

• On Unix, the unix:cmd/1 function could leave an 'EXIT' message in the message queue for the calling process That problem was more likely to happen in an SMP emulator.

  Own Id: OTP-6368

Improvements and New Features

• More interfaces are added in erl_ddll, to support different usage scenarios.

  Own Id: OTP-6307 Aux Id: OTP-6234

• Locks set by calling global:set_lock() were not always deleted when the locking process died. This bug has been fixed.

  Own Id: OTP-6341 Aux Id: seq10445

1.94  Kernel 2.11.2

Fixed Bugs and Malfunctions

• Behavior in case of disappeared nodes when using he dist_auto_connect once got changed in R11B-1. The timeouts regarding normal distributed operations is now reverted to the old (pre R11B-1).

  Own Id: OTP-6258 Aux Id: OTP-6200, seq10449

• Start-up problems for the internal process used by the inet:gethostbyname() functions were eliminated. If the internal process (inet_gethost_native) had not previously been started, and if several processes at the same time called one of the inet:gethostbyname() functions, the calls could fail.

  Own Id: OTP-6286

Improvements and New Features

• Code cleanup: the old internal obsolete file_server has been removed. It was only used when communicating with R7 and older nodes.

  Own Id: OTP-6245

• Trying to open a non-existent or badly formed disk log no longer results in a crash report. In particular, ets:file2tab/1 reports no error when the argument is not a well-formed disk log file. (The return value has not been changed, it is still an error tuple.)

  Own Id: OTP-6278 Aux Id: seq10421

• There are new BIFs erlang:spawn_monitor/1,3, and the new option monitor for spawn_opt/2,3,4,5.

  The observer_backend module has been updated to handle the new BIFs.

  Own Id: OTP-6281

• To help Dialyzer find more bugs, many functions in the Kernel and STDLIB applications now only accept arguments of the type that is documented.

  For instance, the functions lists:prefix/2 and lists:suffix/2 are documented to only accept lists as their arguments, but they actually accepted anything and returned false. That has been changed so that the functions cause an exception if one or both arguments are not lists.

  Also, the string:strip/3 function is documented to take a character argument that is a character to strip from one or both ends of the string. Given a list instead of a character, it used to do nothing, but will now cause an exception.

  Dialyzer will find most cases where those functions are passed arguments of the wrong type.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-6295

1.95  Kernel 2.11.1.1

Improvements and New Features

• There is now an option read_packets for UDP sockets that sets the maximum number of UDP packets that will be read for each invocation of the socket driver.

  Own Id: OTP-6249 Aux Id: seq10452

1.96  Kernel 2.11.1

Fixed Bugs and Malfunctions

• In R11B-0, the erl_ddll server process is always started. Despite that, the configuration parameter start_ddll for the Kernel application was still obeyed, which would cause the erl_ddll server to be started TWICE (and the system shutting down as a result). In this release, start_ddll is no longer used and its documentation has been removed.

  Own Id: OTP-6163

• The kernel option {dist_auto_connect,once} could block out nodes that had never been connected, causing persistent partitioning of networks. Furthermore, partial restarts of networks could cause inconsistent global name databases. Both problems are now solved.

  Own Id: OTP-6200 Aux Id: seq10377

Improvements and New Features

• Late arriving tcp_closed and udp_closed messages are now removed from the message queue of a process calling gen_tcp:close/1, gen_udp:close/1, and inet:close/1.

  Own Id: OTP-6197

1.97  Kernel 2.11

Fixed Bugs and Malfunctions

• When repairing a disk log with a corrupt index file (caused by for instance a hard disk failure) the old contents of the index file is kept unmodified. This will make repeated attempts to open the disk log fail every time.

  Own Id: OTP-5558 Aux Id: seq9823

• Previously unlink/1 and erlang:demonitor/2 behaved completely asynchronous. This had one undesirable effect, though. You could never know when you were guaranteed not to be affected by a link that you had unlinked or a monitor that you had demonitored.

  The new behavior of unlink/1 and erlang:demonitor/2 can be viewed as two operations performed atomically. Asynchronously send an unlink signal or a demonitor signal, and ignore any future results of the link or monitor.

  NOTE: This change can cause some obscure code to fail which previously did not. For example, the following code might hang:

              Mon = erlang:monitor(process, Pid),
              %% ...
              exit(Pid, bang),
              erlang:demonitor(Mon),
              receive
                  {'DOWN', Mon, process, Pid, _} -> ok
              %% We were previously guaranteed to get a down message
              %% (since we exited the process ourself), so we could
              %% in this case leave out:
              %% after 0 -> ok
              end,

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-5772

• The behavior when an application fails to start and possibly causes the runtime system to halt has been cleaned up, including fixing some minor bugs.

  application_controller should now always terminate with a non-nested string, meaning the slogan in an erl_crash.dump should always be easy to read.

  init now makes sure that the slogan passed to erlang:halt/1 does not exceed the maximum allowed length.

  Redundant calls to list_to_atom/1 has been removed from the primitive error_logger event handler. (Thanks Serge Aleynikov for pointing this out).

  The changes only affects the contents of the error messages and crashdump file slogan.

  Own Id: OTP-5964

• The erl_ddll server is now started when OTP is started and placed under the Kernel supervisor. This fixes several minor issues. It used to be started on demand.

  The documentation for the start and stop functions in the erl_ddll module has been removed, as those functions are not meant to be used by other applications.

  Furthermore, the erl_ddll:stop/1 function no longer terminates the erl_ddll server, as that would terminate the entire runtime system.

  Own Id: OTP-6033

Improvements and New Features

• Removed some unused functions from application_master.

  Own Id: OTP-3889

• Global no longer allows the registration of a process under more than one name. If the old (buggy) behavior is desired the Kernel application variable global_multi_name_action can be given the value allow.

  Own Id: OTP-5640 Aux Id: OTP-5603

• The (slightly misleading) warnings that was shown when the erlang.erl file was compiled has been eliminated.

  Own Id: OTP-5947

• The auth module API is deprecated.

  Own Id: OTP-6037

• Added erlang:demonitor/2, making it possible to at the same time flush a received 'DOWN' message, if there is one. See erlang(3).

  Own Id: OTP-6100 Aux Id: OTP-5772

1.98  Kernel 2.10.13

Fixed Bugs and Malfunctions

• Large files (more than 2 GBytes) are now handled on Solaris 8.

  Own Id: OTP-5849 Aux Id: seq10157

• During startup, a garbage {'DOWN', ...} message was left by inet_gethost_native, that caused problems for the starting code server.

  Own Id: OTP-5978 Aux Id: OTP-5974

Improvements and New Features

• global now makes several attempts to connect nodes when maintaining the fully connected network. More than one attempt is sometimes needed under very heavy load.

  Own Id: OTP-5889

• erl_epmd now explicitly sets the timeout to infinity when calling gen_server:call. The old timeout of 15 seconds could time out under very heavy load.

  Own Id: OTP-5959

• Corrected the start of code server to use reference-tagged tuples to ensure that an unexpected message sent to the parent process does not cause a halt of the system. Also removed the useless start/* functions in both code.erl and code_server.erl and no longer exports the init function from code_server.erl.

  Own Id: OTP-5974 Aux Id: seq10243, OTP-5978

1.99  Kernel 2.10.12

Fixed Bugs and Malfunctions

• A bug in global has been fixed: the locker process added nonode@nohost to the list of nodes to lock. This could happen before any nodes got known to the global name server. Depending on net configuration the symptom was a delay.

  Own Id: OTP-5792 Aux Id: OTP-5563

• If an .app file is missing, the error reason returned by application:load/1 has been corrected to {"no such file or directory", "FILE.app"}, instead of the less informative {"unknown POSIX error","FILE.app"}.

  Own Id: OTP-5809

• Bug fixes: disk_log:accessible_logs/0 no longer reports all pg2 process groups as distributed disk logs; disk_log:pid2name/1 did not recognize processes of distributed disk logs.

  Own Id: OTP-5810

• The functions file:consult/1, file:path_consult/2, file:eval/1,2, file:path_eval/2,3, file:script/1,2, file:path_script/2,3 now return correct line numbers in error tuples.

  Own Id: OTP-5814

• If there were user-defined variables in the boot script, and their values were not provided using the -boot_var option, the emulator would refuse to start with a confusing error message. Corrected to show a clear, understandable message.

  The prim_file module was modified to not depend on the lists module, to make it possible to start the emulator using a user-defined loader. (Thanks to Martin Bjorklund.)

  Own Id: OTP-5828 Aux Id: seq10151

• Minor corrections in the description of open modes. (Thanks to Richard Carlsson.)

  Own Id: OTP-5856

Improvements and New Features

• application_controller now terminates with the actual error reason, instead of shutdown. This means that the crash dump now should be somewhat more informative, in the case where the runtime system is terminated due to an error in an application.

  Example: If the (permanent) application app1 fails to start, the slogan now will be: "Kernel pid terminated (application_controller) ({application_start_failure,app1,{shutdown, {app1,start,[normal,[]]}}})"

  rather than the previous "Kernel pid terminated (application_controller) (shutdown)".

  Own Id: OTP-5811

1.100  Kernel 2.10.11.1

Fixed Bugs and Malfunctions

• Timers could sometimes timeout too early. This bug has now been fixed.

  Automatic cancellation of timers created by erlang:send_after(Time, pid(), Msg), and erlang:start_timer(Time, pid(), Msg) has been introduced. Timers created with the receiver specified by a pid, will automatically be cancelled when the receiver exits. For more information see the erlang(3) man page.

  In order to be able to maintain a larger amount of timers without increasing the maintenance cost, the internal timer wheel and bif timer table have been enlarged.

  Also a number of minor bif timer optimizations have been implemented.

  Own Id: OTP-5795 Aux Id: OTP-5090, seq8913, seq10139, OTP-5782

Improvements and New Features

• Documentation improvements:

  - documentation for erlang:link/1 corrected

  - command line flag -code_path_cache added

  - erl command line flags clarifications

  - net_kernel(3) clarifications

  Own Id: OTP-5847

1.101  Kernel 2.10.11

Fixed Bugs and Malfunctions

• Several bug fixes and improvements in the global name registration facility (see global(3)):

  • the name resolving procedure did not always unlink no longer registered processes;
  • the global name could sometimes hang when a nodedown was immediately followed by a nodeup;
  • global names were not always unregistered when a node went down;
  • it is now possible to set and delete locks at the same time as the global name server is resolving names--the handling of global locks has been separated from registration of global names;

  As of this version, global no longer supports nodes running Erlang/OTP R7B or earlier.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-5563

• The functions global:set_lock/3 and global:trans/4 now accept the value 0 (zero) of the Retries argument.

  Own Id: OTP-5737

• The inet:getaddr(Addr, Family) no longer validates the Addr argument if it is a 4 or 8 tuple containing the IP address, except for the size of the tuple and that it contains integers in the correct range.

  The reason for the change is that validation could cause the following sequence of calls to fail:

  {ok,Addr} = inet:getaddr(localhost, inet6), gen_tcp:connect(Addr, 7, [inet6])

  Own Id: OTP-5743

Improvements and New Features

• The previously undocumented and UNSUPPORTED zlib module has been updated in an incompatible way and many bugs have been corrected. It is now also documented.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-5715

• Added application interface functions which_applications/1, set_env/4 and unset_env/3, which take an additional Timeout argument. To be used in situations where the standard gen_server timeout (5000ms) is not adequate.

  Own Id: OTP-5724 Aux Id: seq10083

• Improved documentation regarding synchronized start of applications with included applications (using start phases and application_starter).

  Own Id: OTP-5754

• New socket options priority and tos for platforms that support them (currently only Linux).

  Own Id: OTP-5756

• The global name server has been optimized when it comes to maintaining a fully connected network.

  Own Id: OTP-5770

1.102  Kernel 2.10.10.1

Fixed Bugs and Malfunctions

• The native resolver has gotten an control API for extended debugging and soft restart. It is: inet_gethost_native:control(Control)
  Control = {debug_level,Level} | soft_restart
  Level = integer() in the range 0-4.

  Own Id: OTP-5751 Aux Id: EABln25013

1.103  Kernel 2.10.10

Fixed Bugs and Malfunctions

• If several processes (at the same node) simultaneously tried to start the same distributed application, this could lead to application:start returning an erroneous value, or even hang.

  Own Id: OTP-5606 Aux Id: seq9838

Improvements and New Features

• The manual pages for most of the Kernel and some of the STDLIB modules have been updated, in particular regarding type definitions.

  The documentation of the return value for erts:info/1 has been corrected.

  The documentation for erlang:statistics/1 now lists all possible arguments.

  Own Id: OTP-5360

• When the native resolver fails a gethostbyaddr lookup, nxdomain should be returned. There should be no attempt to fallback on a routine that succeeds if only the syntax of the IP address is valid. This has been fixed.

  Own Id: OTP-5598 Aux Id: OTP-5576

• Replaced some tuple funs with the new fun M:F/A construct.

  The high-order functions in the lists module no longer accept bad funs under any circumstances. 'lists:map(bad_fun, [])' used to return '[]' but now causes an exception.

  Unused, broken compatibility code in the ets module was removed. (Thanks to Dialyzer.)

  Eliminated 5 discrepancies found by Dialyzer in the Appmon application.

  Own Id: OTP-5633

• The possibility to have comments following the list of tuples in a config file (file specified with the -config flag) has been added.

  Own Id: OTP-5661 Aux Id: seq10003

1.104  Kernel 2.10.9

Fixed Bugs and Malfunctions

• 'erl -config sys.config' would fail to start if the sys.config file did not contain any whitespace at all after the dot. (Thanks to Anders Nygren.)

  Own Id: OTP-5543

• A bug regarding tcp sockets which results in hanging gen_tcp:send/2 has been corrected. To encounter this bug you needed one process that read from a socket, one that wrote more date than the reader read out so the sender got suspended, and then the reader closed the socket. (Reported and diagnosed by Alexey Shchepin.)

  Corrected a bug in the (undocumented and unsupported) option {packet,http} for gen_tcp. (Thanks to Claes Wikstrom and Luke Gorrie.)

  Updated the documentation regarding the second argument to gen_tcp:recv/2, the Length to receive.

  Own Id: OTP-5582 Aux Id: seq9839

Improvements and New Features

• At startup, the Erlang resolver hosts table was used to look up the name of the local (and possibly stand alone) host. This was incorrect. The configured resolver method is now used for this purpose.

  Own Id: OTP-5393

• The erlang:port_info/1 BIF is now documented. Minor corrections of the documentation for erlang:port_info/2.

  Added a note to the documentation of the math module that all functions are not available on all platforms.

  Added more information about the +c option in the erl man page in the ERTS documentation.

  Own Id: OTP-5555

• The new fun M:F/A construct creates a fun that refers to the latest version of M:F/A. This syntax is meant to replace tuple funs {M,F} which have many problems.

  The new type test is_function(Fun,A) (which may be used in guards) test whether Fun is a fun that can be applied with A arguments. (Currently, Fun can also be a tuple fun.)

  Own Id: OTP-5584

• According to the documentation global implements the equivalent of register/2, which returns badarg if a process is already registered. As it turns out there is no check in global if a process is registered under more than one name. If some process is accidentally or by design given several names, it is possible that the name registry becomes inconsistent due to the way the resolve function is called when name clashes are discovered (see register_name/3 in global(3)).

  In OTP R11B global will not allow the registration of a process under more than one name. To help finding code where no will be returned, a Kernel application variable, global_multi_name_action, is hereby introduced. Depending on its value (info, warning, or error), messages are sent to the error logger when global discovers that some process is given more than one name. The variable only affects the node where it is defined.

  Own Id: OTP-5603

1.105  Kernel 2.10.8

Improvements and New Features

• In case of a DNS lookup loop, inet_db:getbyname ends up building an infinite list. This has been fixed.

  Own Id: OTP-5449

• When doing an inet6 name lookup on an IPv4 address it was possible to get an address on IPv4 format back. This has been corrected. Some other minor inconsistencies regarding IPv6 name lookup have also been corrected.

  Own Id: OTP-5576

1.106  Kernel 2.10.7

Fixed Bugs and Malfunctions

• Under certain circumstances the net_kernel could emit spurious nodedown messages. This bug has been fixed.

  Own Id: OTP-5396

• Removed description of the keep_zombies configuration parameter in the kernel man page.

  Own Id: OTP-5497

Improvements and New Features

• Eliminated Dialyzer warnings (caused by dead code) in the init and prim_file modules.

  Own Id: OTP-5496

• inet_config now also checks the environment variable ERL_INETRC for a possible user configuration file. See the ERTS User's Guide for details.

  Own Id: OTP-5512

1.107  Kernel 2.10.6

Improvements and New Features

• The c option for the +B flag has been introduced which makes it possible to use Ctrl-C (Ctrl-Break on Windows) to interrupt the shell process rather than to invoke the emulator break handler. All new +B options are also supported on Windows (werl) as of now. Furthermore, Ctrl-C on Windows has now been reserved for copying text (what Ctrl-Ins was used for previously). Ctrl-Break should be used for break handling. Lastly, the documentation of the system flags has been updated.

  Own Id: OTP-5388

• The possibility to start the Erlang shell in parallel with the rest of the system was reintroduced for backwards compatibility in STDLIB 1.13.1. The flag to be used for this is now called async_shell_start and has been documented. New shells started from the JCL menu are not synchronized with init anymore. This makes it possible to start a new shell (e.g. for debugging purposes) even if the initial shell has not come up.

  Own Id: OTP-5406 Aux Id: OTP-5218

1.108  Kernel 2.10.5

Fixed Bugs and Malfunctions

• Documentation for erlang:binary_to_float/1 deleted. The BIF itself was removed several releases ago.

  Updated documentation for apply/2 and apply/3.

  Own Id: OTP-5391

Improvements and New Features

• net_kernel:monitor_nodes/2 which takes a flag and an option list has been added. By use of net_kernel:monitor_nodes/2 one can subscribe for nodeup/nodedown messages with extra information. It is now possible to monitor hidden nodes, and get nodedown reason. See the net_kernel(3) documentation for more information.

  Own Id: OTP-5374

1.109  Kernel 2.10.4

Fixed Bugs and Malfunctions

• The application master for an application now terminates the application faster, which reduces the risk for timeouts in other parts of the system.

  Own Id: OTP-5363 Aux Id: EABln19084

• A BIF erlang:raise/3 has been added. See the manual for details. It is intended for internal system programming only, advanced error handling.

  Own Id: OTP-5376 Aux Id: OTP-5257

1.110  Kernel 2.10.3

Improvements and New Features

• With the -eval flag (erl -eval Expr), an arbitrary expression can be evaluated during system initialization. This is documented in init(3).

  Own Id: OTP-5260

• The unsupported and undocumented modules socks5, socks5_auth, socks5_tcp, and socks5_udp have been removed.

  Own Id: OTP-5266

1.111  Kernel 2.10.1

Fixed Bugs and Malfunctions

• The Pman 'trace shell' functionality was broken and has now been fixed. Furthermore, Pman could not correctly find the pid of the active shell if more than one shell process was running on the node. This has also been corrected.

  Own Id: OTP-5191

• The documentation for the auth:open/1 function which no longer exists has been removed. (Thanks to Miguel Barreiro.)

  Own Id: OTP-5208

• Corrected the crc32/3 function in the undocumented and unsupported zlib module.

  Own Id: OTP-5227

Improvements and New Features

• You can now start Erlang with the -rsh flag which gives you a remote initial shell instead of a local one. Example:

              erl -sname this_node -rsh other_node@other_host
            

  Own Id: OTP-5210

• If /etc/hosts specified two hosts with the same IP address (on separate lines), only the last host would be registered by inet_db during inet configuration. This has been corrected now so that both aliases are registered with the same IP address.

  Own Id: OTP-5212 Aux Id: seq7128

• The documentation for BIFs that take I/O lists have been clarified. Those are list_to_binary/1, port_command/2, port_control/3.

  Documentation for all is_* BIFs (such as is_atom/1) has been added.

  Removed the documentation for erlang:float_to_binary/2 which was removed from the run-time system several releases ago.

  Own Id: OTP-5222