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Updated: Wednesday, July 27, 2022
 
 

env_parallel (1)

Name

env_parallel - export environment to GNU parallel

Synopsis

env_parallel [--record-env|--session|--end-session]
[options for GNU Parallel]

Description

ENV_PARALLEL(1)                    parallel                    ENV_PARALLEL(1)



NAME
       env_parallel - export environment to GNU parallel

SYNOPSIS
       env_parallel [--record-env|--session|--end-session]
         [options for GNU Parallel]

DESCRIPTION
       env_parallel is a shell function that exports the current environment
       to GNU parallel.

       If the shell function is not loaded, a dummy script will be run instead
       that explains how to install the function.

       env_parallel is 100 ms slower at startup than pure GNU parallel, and
       takes up to 30% longer to start a job (typically 15 ms).

       Due to the problem with environment space (see below) the recommended
       usage is either:

         # Do --record-env into $PARALLEL_IGNORED_NAMES
         env_parallel --session

         # Define whatever you want to use
         myfunc() { myalias and functions $myvar work. $1.; }
         alias myalias='echo Aliases'
         myvar='and variables'

         # env_parallel will not export names in $PARALLEL_IGNORED_NAMES
         env_parallel -S localhost myfunc ::: Hooray

       Or:

         # Record the "clean" environment (this only needs to be run once)
         env_parallel --record-env

         # Optionally edit ~/.parallel/ignored_vars (only needed once)

         # Define whatever you want to use
         myfunc() { myalias and functions $myvar work. $1.; }
         alias myalias='echo Aliases'
         myvar='and variables'

         # Use --env _ to only transfer the names not in the "empty" environment
         env_parallel --env _ -S localhost myfunc ::: Hooray

       In csh --session is not supported:

         # Record the "clean" environment - this only needs to be run once
         env_parallel --record-env

         # Optionally edit ~/.parallel/ignored_vars - only needed once

         # Define whatever you want to use
         alias myalias 'echo Aliases $myvar \!*.'
         set myvar='and variables'

         # Use --env _ to only transfer the names not in the "empty" environment
         env_parallel --env _ -S localhost myalias ::: work

   Environment space
       By default env_parallel will export all environment variables, arrays,
       aliases, functions and shell options (see details for the individual
       shells below).

       But this only works if the size of the current environment is smaller
       than the maximal length of a command and smaller than half of the max
       if running remotely. E.g. The max size of Bash's command is 128 KB, so
       env_parallel will fail if 'set | wc -c' is bigger than 128 KB.
       Technically the limit is in execve(1) which IPC::open3 uses.

       Bash completion functions are well-known for taking up well over 128 KB
       of environment space and the primary reason for causing env_parallel to
       fail.

       Instead you can use --env to specify which variables, arrays, aliases
       and functions to export as this will only export those with the given
       name. Or follow the recommended usage in shown in DESCRIPTION.

OPTIONS
       Same as GNU parallel in addition to these:

       --end-session
           Undo last --session

       --record-env
           Record all names currently defined to be ignored every time running
           env_parallel in the future.

       --session
           Ignore all names currently defined. Aliases, variables, arrays, and
           functions currently defined will not be transferred.

           But names defined after running parallel --session will be
           transferred.

           This is only valid in the running shell, and can be undone with
           parallel --end-session.

           You can run multiple --session inside each other:

             env_parallel --session
             var=not
             # var is transferred
             env_parallel -Slocalhost 'echo var is $var' ::: ignored
             env_parallel --session
             # var is not transferred
             env_parallel -Slocalhost 'echo var is $var' ::: ignored
             env_parallel --end-session
             # var is transferred again
             env_parallel -Slocalhost 'echo var is $var' ::: ignored

SUPPORTED SHELLS
   Ash
       Installation

       Put this in $HOME/.profile:

         . `which env_parallel.ash`

       E.g. by doing:

         echo '. `which env_parallel.ash`' >> $HOME/.profile

       Supported use

       --env is supported to export only the variable, or alias with the given
       name. Multiple --envs can be given.

       --session is supported.

       aliases
                 alias myecho='echo aliases'
                 env_parallel myecho ::: work
                 env_parallel -S server myecho ::: work
                 env_parallel --env myecho myecho ::: work
                 env_parallel --env myecho -S server myecho ::: work

                 alias multiline='echo multiline
                   echo aliases'
                 env_parallel multiline ::: work
                 env_parallel -S server multiline ::: work
                 env_parallel --env multiline multiline ::: work
                 env_parallel --env multiline -S server multiline ::: work

       functions
                 ash cannot list defined functions - thus is not supported.

       variables
                 myvar=variables
                 env_parallel echo '$myvar' ::: work
                 env_parallel -S server echo '$myvar' ::: work
                 env_parallel --env myvar echo '$myvar' ::: work
                 env_parallel --env myvar -S server echo '$myvar' ::: work

       arrays  Arrays are not supported by Ash.

   Bash
       Installation

       Put this in $HOME/.bashrc:

         . `which env_parallel.bash`

       E.g. by doing:

         echo '. `which env_parallel.bash`' >> $HOME/.bashrc

       Supported use

       --env is supported to export only the variable, alias, function, or
       array with the given name. Multiple --envs can be given.

       --session is supported.

       aliases
                 alias myecho='echo aliases'
                 env_parallel myecho ::: work
                 env_parallel -S server myecho ::: work
                 env_parallel --env myecho myecho ::: work
                 env_parallel --env myecho -S server myecho ::: work

                 alias multiline='echo multiline
                   echo aliases'
                 env_parallel 'multiline {};
                   echo but only when followed by a newline' ::: work
                 env_parallel -S server 'multiline {};
                   echo but only when followed by a newline' ::: work
                 env_parallel --env multiline 'multiline {};
                   echo but only when followed by a newline' ::: work
                 env_parallel --env multiline -S server 'multiline {};
                   echo but only when followed by a newline' ::: work

       functions
                 myfunc() { echo functions $*; }
                 env_parallel myfunc ::: work
                 env_parallel -S server myfunc ::: work
                 env_parallel --env myfunc myfunc ::: work
                 env_parallel --env myfunc -S server myfunc ::: work

       variables
                 myvar=variables
                 env_parallel echo '$myvar' ::: work
                 env_parallel -S server echo '$myvar' ::: work
                 env_parallel --env myvar echo '$myvar' ::: work
                 env_parallel --env myvar -S server echo '$myvar' ::: work

       arrays
                 myarray=(arrays work, too)
                 env_parallel -k echo '${myarray[{}]}' ::: 0 1 2
                 env_parallel -k -S server echo '${myarray[{}]}' ::: 0 1 2
                 env_parallel -k --env myarray echo '${myarray[{}]}' ::: 0 1 2
                 env_parallel -k --env myarray -S server \
                   echo '${myarray[{}]}' ::: 0 1 2

       BUGS

       Due to a bug in Bash, aliases containing newlines must be followed by a
       newline in the command. Some systems are not affected by this bug, but
       will print a warning anyway.

   csh
       env_parallel for csh breaks $PARALLEL, so do not use $PARALLEL.

       Installation

       Put this in $HOME/.cshrc:

         source `which env_parallel.csh`

       E.g. by doing:

         echo 'source `which env_parallel.csh`' >> $HOME/.cshrc

       Supported use

       --env is supported to export only the variable, alias, or array with
       the given name. Multiple --envs can be given.

       aliases
                 alias myecho 'echo aliases'
                 env_parallel myecho ::: work
                 env_parallel -S server myecho ::: work
                 env_parallel --env myecho myecho ::: work
                 env_parallel --env myecho -S server myecho ::: work

       functions
               Not supported by csh.

       variables
                 set myvar=variables
                 env_parallel echo '$myvar' ::: work
                 env_parallel -S server echo '$myvar' ::: work
                 env_parallel --env myvar echo '$myvar' ::: work
                 env_parallel --env myvar -S server echo '$myvar' ::: work

       arrays with no special chars
                 set myarray=(arrays work, too)
                 env_parallel -k echo \$'{myarray[{}]}' ::: 1 2 3
                 env_parallel -k -S server echo \$'{myarray[{}]}' ::: 1 2 3
                 env_parallel -k --env myarray echo \$'{myarray[{}]}' ::: 1 2 3
                 env_parallel -k --env myarray -S server \
                   echo \$'{myarray[{}]}' ::: 1 2 3

   Dash
       Installation

       Put this in $HOME/.profile:

         . `which env_parallel.dash`

       E.g. by doing:

         echo '. `which env_parallel.dash`' >> $HOME/.profile

       Supported use

       --env is supported to export only the variable, or alias with the given
       name. Multiple --envs can be given.

       --session is supported.

       aliases
                 alias myecho='echo aliases'
                 env_parallel myecho ::: work
                 env_parallel -S server myecho ::: work
                 env_parallel --env myecho myecho ::: work
                 env_parallel --env myecho -S server myecho ::: work

                 alias multiline='echo multiline
                   echo aliases'
                 env_parallel multiline ::: work
                 env_parallel -S server multiline ::: work
                 env_parallel --env multiline multiline ::: work
                 env_parallel --env multiline -S server multiline ::: work

       functions
                 dash cannot list defined functions - thus is not supported.

       variables
                 myvar=variables
                 env_parallel echo '$myvar' ::: work
                 env_parallel -S server echo '$myvar' ::: work
                 env_parallel --env myvar echo '$myvar' ::: work
                 env_parallel --env myvar -S server echo '$myvar' ::: work

       arrays
                 dash does not support arrays.

   fish
       Installation

       Put this in $HOME/.config/fish/config.fish:

         source (which env_parallel.fish)

       E.g. by doing:

         echo 'source (which env_parallel.fish)' \
           >> $HOME/.config/fish/config.fish

       Supported use

       --env is supported to export only the variable, alias, function, or
       array with the given name. Multiple --envs can be given.

       --session is supported.

       aliases
                 alias myecho 'echo aliases'
                 env_parallel myecho ::: work
                 env_parallel -S server myecho ::: work
                 env_parallel --env myecho myecho ::: work
                 env_parallel --env myecho -S server myecho ::: work

       functions
                 function myfunc
                   echo functions $argv
                 end
                 env_parallel myfunc ::: work
                 env_parallel -S server myfunc ::: work
                 env_parallel --env myfunc myfunc ::: work
                 env_parallel --env myfunc -S server myfunc ::: work

       variables
                 set myvar variables
                 env_parallel echo '$myvar' ::: work
                 env_parallel -S server echo '$myvar' ::: work
                 env_parallel --env myvar echo '$myvar' ::: work
                 env_parallel --env myvar -S server echo '$myvar' ::: work

       arrays
                 set myarray arrays work, too
                 env_parallel -k echo '$myarray[{}]' ::: 1 2 3
                 env_parallel -k -S server echo '$myarray[{}]' ::: 1 2 3
                 env_parallel -k --env myarray echo '$myarray[{}]' ::: 1 2 3
                 env_parallel -k --env myarray -S server \
                   echo '$myarray[{}]' ::: 1 2 3

   ksh
       Installation

       Put this in $HOME/.kshrc:

         source `which env_parallel.ksh`

       E.g. by doing:

         echo 'source `which env_parallel.ksh`' >> $HOME/.kshrc

       Supported use

       --env is supported to export only the variable, alias, function, or
       array with the given name. Multiple --envs can be given.

       --session is supported.

       aliases
                 alias myecho='echo aliases'
                 env_parallel myecho ::: work
                 env_parallel -S server myecho ::: work
                 env_parallel --env myecho myecho ::: work
                 env_parallel --env myecho -S server myecho ::: work

                 alias multiline='echo multiline
                   echo aliases'
                 env_parallel multiline ::: work
                 env_parallel -S server multiline ::: work
                 env_parallel --env multiline multiline ::: work
                 env_parallel --env multiline -S server multiline ::: work

       functions
                 myfunc() { echo functions $*; }
                 env_parallel myfunc ::: work
                 env_parallel -S server myfunc ::: work
                 env_parallel --env myfunc myfunc ::: work
                 env_parallel --env myfunc -S server myfunc ::: work

       variables
                 myvar=variables
                 env_parallel echo '$myvar' ::: work
                 env_parallel -S server echo '$myvar' ::: work
                 env_parallel --env myvar echo '$myvar' ::: work
                 env_parallel --env myvar -S server echo '$myvar' ::: work

       arrays
                 myarray=(arrays work, too)
                 env_parallel -k echo '${myarray[{}]}' ::: 0 1 2
                 env_parallel -k -S server echo '${myarray[{}]}' ::: 0 1 2
                 env_parallel -k --env myarray echo '${myarray[{}]}' ::: 0 1 2
                 env_parallel -k --env myarray -S server \
                   echo '${myarray[{}]}' ::: 0 1 2

   mksh
       Installation

       Put this in $HOME/.mkshrc:

         source `which env_parallel.mksh`

       E.g. by doing:

         echo 'source `which env_parallel.mksh`' >> $HOME/.mkshrc

       Supported use

       --env is supported to export only the variable, alias, function, or
       array with the given name. Multiple --envs can be given.

       --session is supported.

       aliases
                 alias myecho='echo aliases'
                 env_parallel myecho ::: work
                 env_parallel -S server myecho ::: work
                 env_parallel --env myecho myecho ::: work
                 env_parallel --env myecho -S server myecho ::: work

                 alias multiline='echo multiline
                   echo aliases'
                 env_parallel multiline ::: work
                 env_parallel -S server multiline ::: work
                 env_parallel --env multiline multiline ::: work
                 env_parallel --env multiline -S server multiline ::: work

       functions
                 myfunc() { echo functions $*; }
                 env_parallel myfunc ::: work
                 env_parallel -S server myfunc ::: work
                 env_parallel --env myfunc myfunc ::: work
                 env_parallel --env myfunc -S server myfunc ::: work

       variables
                 myvar=variables
                 env_parallel echo '$myvar' ::: work
                 env_parallel -S server echo '$myvar' ::: work
                 env_parallel --env myvar echo '$myvar' ::: work
                 env_parallel --env myvar -S server echo '$myvar' ::: work

       arrays
                 myarray=(arrays work, too)
                 env_parallel -k echo '${myarray[{}]}' ::: 0 1 2
                 env_parallel -k -S server echo '${myarray[{}]}' ::: 0 1 2
                 env_parallel -k --env myarray echo '${myarray[{}]}' ::: 0 1 2
                 env_parallel -k --env myarray -S server \
                   echo '${myarray[{}]}' ::: 0 1 2

   pdksh
       Installation

       Put this in $HOME/.profile:

         source `which env_parallel.pdksh`

       E.g. by doing:

         echo 'source `which env_parallel.pdksh`' >> $HOME/.profile

       Supported use

       --env is supported to export only the variable, alias, function, or
       array with the given name. Multiple --envs can be given.

       --session is supported.

       aliases
                 alias myecho="echo aliases";
                 env_parallel myecho ::: work;
                 env_parallel -S server myecho ::: work;
                 env_parallel --env myecho myecho ::: work;
                 env_parallel --env myecho -S server myecho ::: work

       functions
                 myfunc() { echo functions $*; };
                 env_parallel myfunc ::: work;
                 env_parallel -S server myfunc ::: work;
                 env_parallel --env myfunc myfunc ::: work;
                 env_parallel --env myfunc -S server myfunc ::: work

       variables
                 myvar=variables;
                 env_parallel echo "\$myvar" ::: work;
                 env_parallel -S server echo "\$myvar" ::: work;
                 env_parallel --env myvar echo "\$myvar" ::: work;
                 env_parallel --env myvar -S server echo "\$myvar" ::: work

       arrays
                 myarray=(arrays work, too);
                 env_parallel -k echo "\${myarray[{}]}" ::: 0 1 2;
                 env_parallel -k -S server echo "\${myarray[{}]}" ::: 0 1 2;
                 env_parallel -k --env myarray echo "\${myarray[{}]}" ::: 0 1 2;
                 env_parallel -k --env myarray -S server \
                   echo "\${myarray[{}]}" ::: 0 1 2

   sh
       Installation

       Put this in $HOME/.profile:

         . `which env_parallel.sh`

       E.g. by doing:

         echo '. `which env_parallel.sh`' >> $HOME/.profile

       Supported use

       --env is supported to export only the variable, or alias with the given
       name. Multiple --envs can be given.

       --session is supported.

       aliases
                 sh does not support aliases.

       functions
                 myfunc() { echo functions $*; }
                 env_parallel myfunc ::: work
                 env_parallel -S server myfunc ::: work
                 env_parallel --env myfunc myfunc ::: work
                 env_parallel --env myfunc -S server myfunc ::: work

       variables
                 myvar=variables
                 env_parallel echo '$myvar' ::: work
                 env_parallel -S server echo '$myvar' ::: work
                 env_parallel --env myvar echo '$myvar' ::: work
                 env_parallel --env myvar -S server echo '$myvar' ::: work

       arrays
                 sh does not support arrays.

   tcsh
       env_parallel for tcsh breaks $PARALLEL, so do not use $PARALLEL.

       Installation

       Put this in $HOME/.tcshrc:

         source `which env_parallel.tcsh`

       E.g. by doing:

         echo 'source `which env_parallel.tcsh`' >> $HOME/.tcshrc

       Supported use

       --env is supported to export only the variable, alias, or array with
       the given name. Multiple --envs can be given.

       aliases
                 alias myecho 'echo aliases'
                 env_parallel myecho ::: work
                 env_parallel -S server myecho ::: work
                 env_parallel --env myecho myecho ::: work
                 env_parallel --env myecho -S server myecho ::: work

       functions
               Not supported by tcsh.

       variables
                 set myvar=variables
                 env_parallel echo '$myvar' ::: work
                 env_parallel -S server echo '$myvar' ::: work
                 env_parallel --env myvar echo '$myvar' ::: work
                 env_parallel --env myvar -S server echo '$myvar' ::: work

       arrays with no special chars
                 set myarray=(arrays work, too)
                 env_parallel -k echo \$'{myarray[{}]}' ::: 1 2 3
                 env_parallel -k -S server echo \$'{myarray[{}]}' ::: 1 2 3
                 env_parallel -k --env myarray echo \$'{myarray[{}]}' ::: 1 2 3
                 env_parallel -k --env myarray -S server \
                   echo \$'{myarray[{}]}' ::: 1 2 3

   Zsh
       Installation

       Put this in $HOME/.zshrc:

         . `which env_parallel.zsh`

       E.g. by doing:

         echo '. `which env_parallel.zsh`' >> $HOME/.zshenv

       Supported use

       --env is supported to export only the variable, alias, function, or
       array with the given name. Multiple --envs can be given.

       --session is supported.

       aliases
                 alias myecho='echo aliases'
                 env_parallel myecho ::: work
                 env_parallel -S server myecho ::: work
                 env_parallel --env myecho myecho ::: work
                 env_parallel --env myecho -S server myecho ::: work

                 alias multiline='echo multiline
                   echo aliases'
                 env_parallel multiline ::: work
                 env_parallel -S server multiline ::: work
                 env_parallel --env multiline multiline ::: work
                 env_parallel --env multiline -S server multiline ::: work

       functions
                 myfunc() { echo functions $*; }
                 env_parallel myfunc ::: work
                 env_parallel -S server myfunc ::: work
                 env_parallel --env myfunc myfunc ::: work
                 env_parallel --env myfunc -S server myfunc ::: work

       variables
                 myvar=variables
                 env_parallel echo '$myvar' ::: work
                 env_parallel -S server echo '$myvar' ::: work
                 env_parallel --env myvar echo '$myvar' ::: work
                 env_parallel --env myvar -S server echo '$myvar' ::: work

       arrays
                 myarray=(arrays work, too)
                 env_parallel -k echo '${myarray[{}]}' ::: 1 2 3
                 env_parallel -k -S server echo '${myarray[{}]}' ::: 1 2 3
                 env_parallel -k --env myarray echo '${myarray[{}]}' ::: 1 2 3
                 env_parallel -k --env myarray -S server \
                   echo '${myarray[{}]}' ::: 1 2 3

EXIT STATUS
       Same as GNU parallel.

AUTHOR
       When using GNU env_parallel for a publication please cite:

       O. Tange (2018): GNU Parallel 2018, March 2018, ISBN 9781387509881,
       DOI: 10.5281/zenodo.1146014.

       This helps funding further development; and it won't cost you a cent.
       If you pay 10000 EUR you should feel free to use GNU Parallel without
       citing.

       Copyright (C) 2007-10-18 Ole Tange, http://ole.tange.dk

       Copyright (C) 2008-2010 Ole Tange, http://ole.tange.dk

       Copyright (C) 2010-2021 Ole Tange, http://ole.tange.dk and Free
       Software Foundation, Inc.

LICENSE
       This program is free software; you can redistribute it and/or modify it
       under the terms of the GNU General Public License as published by the
       Free Software Foundation; either version 3 of the License, or at your
       option any later version.

       This program is distributed in the hope that it will be useful, but
       WITHOUT ANY WARRANTY; without even the implied warranty of
       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
       General Public License for more details.

       You should have received a copy of the GNU General Public License along
       with this program.  If not, see <http://www.gnu.org/licenses/>.

   Documentation license I
       Permission is granted to copy, distribute and/or modify this
       documentation under the terms of the GNU Free Documentation License,
       Version 1.3 or any later version published by the Free Software
       Foundation; with no Invariant Sections, with no Front-Cover Texts, and
       with no Back-Cover Texts.  A copy of the license is included in the
       file LICENSES/GFDL-1.3-or-later.txt.

   Documentation license II
       You are free:

       to Share to copy, distribute and transmit the work

       to Remix to adapt the work

       Under the following conditions:

       Attribution
                You must attribute the work in the manner specified by the
                author or licensor (but not in any way that suggests that they
                endorse you or your use of the work).

       Share Alike
                If you alter, transform, or build upon this work, you may
                distribute the resulting work only under the same, similar or
                a compatible license.

       With the understanding that:

       Waiver   Any of the above conditions can be waived if you get
                permission from the copyright holder.

       Public Domain
                Where the work or any of its elements is in the public domain
                under applicable law, that status is in no way affected by the
                license.

       Other Rights
                In no way are any of the following rights affected by the
                license:

                o Your fair dealing or fair use rights, or other applicable
                  copyright exceptions and limitations;

                o The author's moral rights;

                o Rights other persons may have either in the work itself or
                  in how the work is used, such as publicity or privacy
                  rights.

       Notice   For any reuse or distribution, you must make clear to others
                the license terms of this work.

       A copy of the full license is included in the file as
       LICENCES/CC-BY-SA-4.0.txt

DEPENDENCIES
       env_parallel uses GNU parallel.


ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       +---------------+------------------+
       |ATTRIBUTE TYPE | ATTRIBUTE VALUE  |
       +---------------+------------------+
       |Availability   | shell/parallel   |
       +---------------+------------------+
       |Stability      | Uncommitted      |
       +---------------+------------------+

SEE ALSO
       parallel(1), ash(1), bash(1), csh(1), dash(1), fish(1), ksh(1),
       pdksh(1) tcsh(1), zsh(1).



NOTES
       Source code for open source software components in Oracle Solaris can
       be found at https://www.oracle.com/downloads/opensource/solaris-source-
       code-downloads.html.

       This software was built from source available at
       https://github.com/oracle/solaris-userland.  The original community
       source was downloaded from
       https://ftp.gnu.org/gnu/parallel/parallel-20211122.tar.bz2.

       Further information about this software can be found on the open source
       community website at https://www.gnu.org/software/parallel.



20211122                          2021-11-22                   ENV_PARALLEL(1)