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The release resource file describes each release of an entire system based on OTP. This file defines which applications are included in a certain version of the system.
This file is used by systools to generate start scripts
and release upgrade files.
Releases can also be upgraded and instructions for this should
be written in the relup file (see the definition of the
relup file). The tedious work of writing the relup file
has been automated and in most cases the file can be
automatically generated from the .appup files for the
applications in the release.
A release resource file is called RelName.rel where
RelName is the name of the release.
The .rel file contains one single Erlang term, which is
called a release specification. The file has the
following syntax:
{release, {Name,Vsn}, {erts, EVsn},
[{AppName, AppVsn} |
{AppName, AppVsn, AppType} |
{AppName, AppVsn, IncApps} |
{AppName, AppVsn, AppType, IncApps}]}.
Name = string() is the name of the release Name
need not be the same as RelName above in
the file name.
Vsn = string() is the version of the release.
EVsn = string() indicates which Erlang runtime system
version EVsn the release is intended for, for example
"4.4".
AppName = atom() is the name of an application included in
the release.
AppVsn = string() is the version of the AppName
application.
AppType = permanent | transient | temporary | load |
none is the start type of the AppName
application. This parameter specifies how the application is
treated in the systools-generated start script. If it is
permanent, transient or temporary, the
application is started with a call to
application:start(AppName, AppType). If it is
load, the application is loaded, but not started. If
it is none, the application is neither loaded nor started.
IncApps = [atom()] is a list of applications
that are included by an application, for example [AppName,
...]. This list overrides the
included_applications key in the application resource
file .app. This list must be a subset of the list of
included applications which are specified in the .app
file.
 |
The list of applications must contain the |
app(4), appup(4), relup(4), systools(3)