GNU Parallel with environment

NAME
env_parallel - export environment to GNU parallelSYNOPSIS
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 thefunction.
env_parallel is 100 ms slower at startup than pure GNU parallel, and takes up to 30% longer to starta job (typically 15 ms).
Due to the problem with environment space (see below) you are recommended only to transfer theenvironment that you need.
To help you do that, you can mark names that should not be transferred. This can be done with either--session or --record-env.
# 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
Or:# 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# Optionallyenv_parallel --end-session
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
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GNU Parallel with environment# 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 acommand and smaller than half of the max if running remotely. E.g. The max size of Bash's commandis 128 KB, so env_parallel will fail if 'set | wc -c' is bigger than 128 KB. Technically the limit is inexecve(1) which IPC::open3 uses.
Bash completion functions are well-known for taking up well over 128 KB of environment space andthe primary reason for causing env_parallel to fail.
Instead you can use --env to specify which variables, arrays, aliases and functions to export as thiswill only export those with the given name. Or follow the recommended usage in shown in
DESCRIPTION.

OPTIONSSame 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 SHELLSAshPage 2

GNU Parallel with environment
Installation
Put this in $HOME/.profile:. env_parallel.ash
E.g. by doing:echo '. env_parallel.ash' >> $HOME/.profile
Supported use--env is supported to export only the variable, or alias with the given name. Multiple --envs can begiven.
--session is supported.
aliasesalias myecho='echo aliases'
env_parallel myecho ::: work
env_parallel -S server myecho ::: work
env_parallel --env myecho myecho ::: work
env_parallel --env myecho -S server myecho ::: work
alias multiline='echo multiline
echo aliases'
env_parallel multiline ::: work
env_parallel -S server multiline ::: work
env_parallel --env multiline multiline ::: work
env_parallel --env multiline -S server multiline ::: work
functionsash cannot list defined functions - thus is not supported.
variables
myvar=variables
env_parallel echo '$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
arraysArrays are not supported by Ash.

Bash
Installation
Put this in $HOME/.bashrc:. env_parallel.bash
E.g. by doing:echo '. env_parallel.bash' >> $HOME/.bashrc

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GNU Parallel with environment
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.
aliasesalias 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 '$myvar' ::: work
arraysmyarray=(arrays work, too)
env_parallel -k echo '${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 (beta testing)
env_parallel for csh breaks $PARALLEL, so do not use $PARALLEL.

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GNU Parallel with environment
Installation
Put this in $HOME/.cshrc:
source `which env_parallel.csh`
E.g. by doing:echo 'source `which env_parallel.csh`' >> $HOME/.cshrc
Supported use--env is supported to export only the variable, alias, or array with the given name. Multiple --envs canbe given.
aliasesalias myecho 'echo aliases'
env_parallel myecho ::: work
env_parallel -S server myecho ::: work
env_parallel --env myecho myecho ::: work
env_parallel --env myecho -S server myecho ::: work
functions
Not supported by csh.
variables
set myvar=variables
env_parallel echo '$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

DashInstallation
Put this in $HOME/.profile:. env_parallel.dash
E.g. by doing:echo '. env_parallel.dash' >> $HOME/.profile
Supported use--env is supported to export only the variable, or alias with the given name. Multiple --envs can begiven.
--session is supported.

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GNU Parallel with environment
aliasesalias 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
functionsdash 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
arraysdash 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.
aliasesalias 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
functionsfunction myfunc
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GNU Parallel with environment
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 '$myvar' ::: work
arraysArrays normally work, but fail intermitently.
set myarray arrays work, too
env_parallel -k echo '$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 3ksh
Installation
Put this in $HOME/.kshrc:
source env_parallel.ksh
E.g. by doing:echo 'source 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.
aliasesalias 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
functionsPage 7

GNU Parallel with environment
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 '$myvar' ::: work
arraysmyarray=(arrays work, too)
env_parallel -k echo '${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 env_parallel.mksh
E.g. by doing:echo 'source 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.
aliasesalias 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 $*; }env_parallel myfunc ::: work
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GNU Parallel with environment
env_parallel -S server myfunc ::: work
env_parallel --env myfunc myfunc ::: work
env_parallel --env myfunc -S server myfunc ::: work
variables
myvar=variables
env_parallel echo '$myvar' ::: work
env_parallel -S server echo '$myvar' ::: work
env_parallel --env myvar echo '$myvar' ::: work
env_parallel --env myvar -S server echo '$myvar' ::: work
arraysmyarray=(arrays work, too)
env_parallel -k echo '${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 env_parallel.pdksh
E.g. by doing:echo 'source 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.
aliasesalias 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;
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GNU Parallel with environment
env_parallel --env myvar echo "\$myvar" ::: work;
env_parallel --env myvar -S server echo "\$myvar" ::: work
arraysmyarray=(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 12;
env_parallel -k --env myarray -S server \echo "\${myarray[{}]}" ::: 0 1 2

shInstallation
Put this in $HOME/.profile:. env_parallel.sh
E.g. by doing:echo '. env_parallel.sh' >> $HOME/.profile
Supported use--env is supported to export only the variable, or alias with the given name. Multiple --envs can begiven.
--session is supported.
aliasessh 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
arrayssh does not support arrays.

tcsh (beta testing)
env_parallel for tcsh breaks $PARALLEL, so do not use $PARALLEL.

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GNU Parallel with environment
Installation
Put this in $HOME/.tcshrc:
source `which env_parallel.tcsh`
E.g. by doing:echo 'source `which env_parallel.tcsh`' >> $HOME/.tcshrc
Supported use--env is supported to export only the variable, alias, or array with the given name. Multiple --envs canbe given.
aliasesalias myecho 'echo aliases'
env_parallel myecho ::: work
env_parallel -S server myecho ::: work
env_parallel --env myecho myecho ::: work
env_parallel --env myecho -S server myecho ::: work
functions
Not supported by tcsh.
variables
set myvar=variables
env_parallel echo '$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:. env_parallel.zsh
E.g. by doing:echo '. 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.

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GNU Parallel with environment
aliasesalias 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 '$myvar' ::: work
arraysmyarray=(arrays work, too)
env_parallel -k echo '${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) 2010-2024 Ole Tange, http://ole.tange.dk and Free Software Foundation, Inc.

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GNU Parallel with environment

LICENSEThis 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 theLicense, or at your option any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; withouteven 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 Shareto 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 notin any way that suggests that they endorse you or your use of the work).
Share AlikeIf 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:
WaiverAny of the above conditions can be waived if you get permission from the copyrightholder.
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:
Your fair dealing or fair use rights, or other applicable copyright exceptions andlimitations;
The author's moral rights;
Rights other persons may have either in the work itself or in how the work isused, such as publicity or privacy rights.
NoticePage 13

GNU Parallel with environment
For any reuse or distribution, you must make clear to others the license terms of thiswork.
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.

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

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