erlc

erlc

Compiler

The erlc program provides a common way to run all compilers in the Erlang system. Depending on the extension of each input file, erlc will invoke the appropriate compiler. Regardless of which compiler is used, the same flags are used to provide parameters such as include paths and output directory.

Erlc compiles one or more files. The files must include the extension, for example .erl for Erlang source code, or .yrl for Yecc source code. Erlc uses the extension to invoke the correct compiler.

The following flags are supported:

-I directory

Instructs the compiler to search for include files in the specified directory. When encountering an -include or -include_dir directive, the compiler searches for header files in the following directories:

1. ".", the current working directory of the file server;
   
2. the base name of the compiled file;
   
3. the directories specified using the -I option. The directory specified last is searched first.
   

-o directory

The directory where the compiler should place the output files. If not specified, output files will be placed in the current working directory.

-Dname

Defines a macro.

-Dname=value

Defines a macro with the given value. The value can be any Erlang term. Depending on the platform, the value may need to be quoted if the shell itself interprets certain characters. On Unix, terms which contain tuples and list must be quoted. Terms which contain spaces must be quoted on all platforms.

-Wnumber

Sets warning level to number. Default is 1. Use -W0 to turn off warnings.

-W

Same as -W1. Default.

-v

Enables verbose output.

-b output-type

Specifies the type of output file. Generally, output-type is the same as the file extension of the output file but without the period. This option will be ignored by compilers that have a a single output format.

--

Signals that no more options will follow. The rest of the arguments will be treated as file names, even if they start with hyphens.

+term

A flag starting with a plus ('+') rather than a hyphen will be converted to an Erlang term and passed unchanged to the compiler. For instance, the export_all option for the Erlang compiler can be specified as follows:

erlc +export_all file.erl
    

Depending on the platform, the value may need to be quoted if the shell itself interprets certain characters. On Unix, terms which contain tuples and list must be quoted. Terms which contain spaces must be quoted on all platforms.

The flags in this section are useful in special situations such as re-building the OTP system.

-pa directory

Appends directory to the front of the code path in the invoked Erlang emulator. This can be used to invoke another compiler than the default one.

-pz directory

Appends directory to the code path in the invoked Erlang emulator.

.erl

Erlang source code. It generates a .beam file.
The options -P, -E, and -S are equivalent to +'P', +'E', and +'S', except that it is not necessary to include the single quotes to protect them from the shell.
Supported options: -I, -o, -D, -v, -W, -b.

.yrl

Yecc source code. It generates an .erl file.
Use the -I option with the name of a file to use that file as a customized prologue file (the includefile option).
Supported options: -o, -v, -I, -W (see above).

.mib

MIB for SNMP. It generates a .bin file.
Supported options: -I, -o, -W.

.bin

A compiled MIB for SNMP. It generates a .hrl file.
Supported options: -o, -v.

.rel

Script file. It generates a boot file.
Use the -I to name directories to be searched for application files (equivalent to the path in the option list for systools:make_script/2).
Supported options: -o.

.asn1

ASN1 file.
Creates an .erl, .hrl, and .asn1db file from an .asn1 file. Also compiles the .erl using the Erlang compiler unless the +noobj options is given.
Supported options: -I, -o, -b, -W.

.idl

IC file.
Runs the IDL compiler.
Supported options: -I, -o.

ERLC_EMULATOR

The command for starting the emulator. Default is erl in the same directory as the erlc program itself, or if it doesn't exist, erl in any of the directories given in the PATH environment variable.

erl(1), compile(3), yecc(3), snmp(3)

Björn Gustavsson - support@erlang.ericsson.se