start_erl - Start Erlang for embedded systems on Windows systems.
Please see following description for synopsis
start_erl(1) User Commands start_erl(1)
NAME
start_erl - Start Erlang for embedded systems on Windows systems.
DESCRIPTION
The start_erl program is specific to Windows NT/2000/XP (and later ver-
sions of Windows). Although there are programs with the same name on
other platforms, their functionality is different.
This program is distributed both in compiled form (under <Erlang
root>\\erts-<version>\\bin) and in source form (under <Erlang
root>\\erts-<version>\\src). The purpose of the source code is to ease
customization of the program for local needs, such as cyclic restart
detection. There is also a "make"-file, written for the nmake program
distributed with Microsoft Visual C++. This program can, however, be
compiled with any Win32 C compiler (possibly with minor modifications).
This program aids release handling on Windows systems. The program is
to be called by the erlsrv program, read up the release data file
start_erl.data, and start Erlang. Some options to start_erl are added
and removed by the release handler during upgrade with emulator restart
(more specifically option -data).
EXPORTS
start_erl [<erl options>] ++ [<start_erl options>]
The start_erl program in its original form recognizes the fol-
lowing options:
++:
Mandatory. Delimits start_erl options from normal Erlang
options. Everything on the command line before ++ is inter-
preted as options to be sent to the erl program. Everything
after ++ is interpreted as options to start_erl itself.
-reldir <release root>:
Mandatory if environment variable RELDIR is not specified
and no -rootdir option is specified. Tells start_erl where
the root of the release tree is located in the file system
(typically <Erlang root>\\releases). The start_erl.data file
is expected to be located in this directory (unless other-
wise specified). If only option -rootdir is specified, the
directory is assumed to be <Erlang root>\\releases.
-rootdir <Erlang root directory>:
Mandatory if -reldir is not specified and no RELDIR exists
in the environment. This specifies the Erlang installation
root directory (under which the lib, releases, and
erts-<Version> directories are located). If only -reldir (or
environment variable RELDIR) is specified, the Erlang root
is assumed to be the directory exactly one level above the
release directory.
-data <data file name>:
Optional. Specifies another data file than start_erl.data in
the <release root>. It is specified relative to the <release
root> or absolute (including drive letter, and so on). This
option is used by the release handler during upgrade and is
not to be used during normal operation. Normally the release
data file is not to be named differently.
-bootflags <boot flags file name>:
Optional. Specifies a file name relative to the release
directory (that is, the subdirectory of <release root> where
the .boot file and others are located). The contents of this
file is appended to the command line when Erlang is started.
This makes it easy to start the emulator with different
options for different releases.
NOTES
* As the source code is distributed, it can easily be modified to
accept other options. The program must still accept option -data
with the semantics described above for the release handler to work
correctly.
* The Erlang emulator is found by examining the registry keys for the
emulator version specified in the release data file. The new emula-
tor must be properly installed before the upgrade for this to work.
* Although the program is located together with files specific to the
emulator version, it is not expected to be specific to the emulator
version. The release handler does not change option -machine to
erlsrv during emulator restart. Locate the (possibly customized)
start_erl program so that it is not overwritten during upgrade.
* The default options of the erlsrv program are not sufficient for
release handling. The machine started by erlsrv is be specified as
the start_erl program and the arguments are to contain ++ followed
by the desired options.
SEE ALSO
erlsrv(1), release_handler(3)
Ericsson AB erts 8.3 start_erl(1)