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Updated: July 2014

start_erl (1)


start_erl - Start Erlang for embedded systems on Windows NT(R)


Please see following description for synopsis


User Commands                                        start_erl(1)

     start_erl  -  Start  Erlang  for embedded systems on Windows

     This describes the start_erl program specific to Windows NT.
     Although  there  exists programs with the same name on other
     platforms, their functionality is not the same.

     The start_erl 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 make it possible to easily cus-
     tomize the program for local needs, such as  cyclic  restart
     detection  etc. There is also a "make"-file, written for the
     nmake program distributed with Microsoft(R)  Visual  C++(R).
     The  program  can  however be compiled with any Win32 C com-
     piler (possibly with slight modifications).

     The purpose of the program is to  aid  release  handling  on
     Windows  NT(R).  The  program should be called by the erlsrv
     program, read up the release data  file  and
     start  Erlang.  Certain  options  to start_erl are added and
     removed by the release handler during upgrade with  emulator
     restart (more specifically the -data option).

     start_erl [<erl options>] ++ [<start_erl options>]

          The  start_erl  program in its original form recognizes
          the following options:

              Mandatory, delimits start_erl options  from  normal
              Erlang  options.  Everything  on  the  command line
              before the ++ is interpreted as options to be  sent
              to  the  erl  program. Everything after++ is inter-
              preted as options to start_erl itself.

            -reldir <release root>:
              Mandatory if the environment variable RELDIR is not
              specified  and  no  -rootdir option is given. Tells
              start_erl where the root of  the  release  tree  is
              placed   in   the  file-system  (typically  <Erlang
              root>\\releases).  The   file   is
              expected  to  be  placed  in this directory (if not
              otherwise specified). If only the  -rootdir  option
              is  given,  the  directory is assumed to be <Erlang

            -rootdir <Erlang root directory>:
              Mandatory if -reldir is not given and there  is  no

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User Commands                                        start_erl(1)

              RELDIR  in  the  environment.  This  specifies  the
              Erlang installation root directory (under which the
              lib,  releases  and  erts-<Version> directories are
              placed). If only -reldir (or the environment  vari-
              able  RELDIR)  is given, 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
     in the <release root>. It is  speci-
              fied  relative  to  the  <release root> or absolute
              (including drive letter etc.). This option is  used
              by  the  release  handler during upgrade and should
              not be used during normal  operation.  The  release
              data file should not normally be named differently.

            -bootflags <boot flags file name>:
              Optional, specifies a file name relative to  actual
              release  directory  (that  is  the  subdirectory of
              <release  root>  where  the  .boot  file  etc.  are
              placed).  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.

     See  attributes(5)  for  descriptions   of   the   following

     |Availability   | runtime/erlang   |
     |Stability      | Uncommitted      |
     As the source code is distributed, it can easily be modified
     to accept other options. The program must still  accept  the
     -data  option  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 emulator needs to be properly installed  before  the
     upgrade for this to work.

     Although the program is located together with files specific
     to emulator version, it is not expected to  be  specific  to
     the  emulator  version.  The release handler does not change

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User Commands                                        start_erl(1)

     the -machine option to erlsrv during emulator restart. Place
     the  (possibly  customized)  start_erl program so that it is
     not overwritten during upgrade.

     The erlsrv program's default options are not sufficient  for
     release handling. The machine erlsrv starts should be speci-
     fied as the start_erl program and the arguments should  con-
     tain the ++ followed by desired options.

     erlsrv(1), release_handler(3)

     This   software   was   built   from   source  available  at   The   original
     community       source       was       downloaded       from

     Further information about this software can be found on  the
     open source community website at

Ericsson AB         Last change: erts                   3