PAR::Environment(3)

👑 PAR::Environment 💖 — the whole vibe check on PAR's environment variables

Hiii bestie, welcome to PAR::Environment (that's the manual page, and yes it's a 3, section three of the perl docs, iykyk). This is your one-stop group chat for every env var PAR touches. Let's get into it 🦋

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🌸 NAME 🌸

PAR::Environment — the index and reference of PAR environment variables. That's it, that's the whole name, periodt.

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💅 DESCRIPTION 💅

So, PAR uses a whole bunch of environment variables — both while it's building executables or PAR archives and while it's using them. And because the sheer number of combinations and settings out there might confuse one or the other person (lowkey including me, fr), this document exists to document all the environment variables that PAR uses.

Whenever I want to refer to the $ENV{FOO} environment hash entry, I'll usually just call it the "FOO" variable, for brevity. Short queen energy ✨

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🎀 INDEX OF ENVIRONMENT VARIABLES 🎀

Heads up bestie: this is still very, very incomplete! Contributions welcome! 🫶

For each variable, there should be:

• a description of what it contains,
• when it can be expected to exist (and contain meaningful info),
• when it's sensible to define it yourself,
• and what effect that has.

And of course, the descriptions may use examples. Slay.

🍓 PAR_0

If the running program is run from within a PAR archive or a pp-produced executable, this variable holds the name of the extracted program (i.e. the .pl file). Super useful if you want to open the source code file of the running program 👑

For example, if you package a file foo.pl into bar.par and run foo.pl with this command:

par.pl foo.par bar.pl

then the "PAR_0" variable will contain something like

/tmp/par-youser/cache-b175f53eb731da9594e0dde337d66013ddf25a44/495829f0.pl

where "youser" is your username and /tmp/par-youser/cache-b175f53eb731da9594e0dde337d66013ddf25a44/ is the PAR cache directory ("PAR_TEMP").

The name of the PAR cache directory can take a number of different forms, so use "PAR_0" if you want to find the extracted program's .pl file — attempting to construct the name yourself requires complex logic that has already produced the value in "PAR_0". Don't do the math yourself bestie, the value is right there 💀

This works the same for executable binaries (.exe, ...).

If you're looking for the name and path of the pp-ed binary file, please refer to the "PAR_PROGNAME" variable instead 🔥

🌈 PAR_CLEAN

Users should set "PAR_GLOBAL_CLEAN" instead.

Recreated from "PAR_GLOBAL_CLEAN" and the value of -C from the YAML file by the PAR loader, and used within the loader to control the initial behavior of extraction, and the final behavior of cleanup. The user can reference "PAR_CLEAN" in the application to determine which of these behaviors is being used for this run of the application.

🦋 PAR_DEBUG

Users should set "PAR_GLOBAL_DEBUG" instead.

If this variable is set to a true value and par.pl is run, verbose output is sent to STDOUT or the logging filehandle. This is overridden by the -q option to par.pl, for steps after argument parsing occurs.

This currently only influences par.pl. Whether this is the intended behaviour remains to be verified. 🙈 (iconic, honestly)

💜 PAR_GLOBAL_CLEAN

Setting "PAR_GLOBAL_CLEAN" alters the behavior of par applications which see that environment variable at launch. "PAR_GLOBAL_CLEAN" overrides the -C option. Settings of 0 and 1 are supported. 0 corresponds to not using -C on the pp command line; 1 corresponds to using -C on the pp command line. "PAR_GLOBAL_CLEAN" is ignored if "PAR_GLOBAL_TEMP" is set, yet it controls the form of "PAR_TEMP" when "PAR_GLOBAL_TEMP" is not set.

⭐ PAR_GLOBAL_DEBUG

The PAR loader becomes more verbose when "PAR_DEBUG" is set. Setting "PAR_GLOBAL_DEBUG" guarantees that "PAR_DEBUG" will be set internally, initially. See "PAR_DEBUG" for more details.

🧚 PAR_GLOBAL_TEMP

Contributes to the calculation of "PAR_TEMP", and is further explained there.

🌸 PAR_GLOBAL_TMPDIR

Contributes to the calculation of "PAR_TEMP", and is further explained there.

💖 PAR_INITIALIZED

This environment variable is for internal use by the PAR binary loader only. Documented only to avoid surprises if spawned applications expect to see a value initialized by the user.

🎀 PAR_PROGNAME

"PAR_PROGNAME" is set to the fully-qualified path name of the executable program. On Windows, this is reliably obtained from the GetModuleFileName API. On other OSes, if the C runtime is given a qualified path name, it is used, or the unqualified file name given is qualified by walking the path. This is reasonably reliable given normal program spawning conventions, but cannot be guaranteed to be correct in all circumstances.

🔥 PAR_APP_REUSE

Strictly internal. Skip this section if you're not a PAR developer.

The variable shouldn't ever be exposed to user code and packaged applications should not depend on it being set or not.

If an application has been packaged with the --reusable option, the bootstrapping code will set this environment variable to the name of the program that is to be run instead of the packaged program. The main.pl loader script fetches the file name, deletes the environment variable, and then runs the given program.

💀 PAR_RUN

This environment variable was set during constructions of PAR::Packer objects (usually during pp runs only) by versions of PAR up to 0.957. Since PAR 0.958, this variable is unused. Rip to it, honestly 🪦

🙈 PAR_SPAWNED

This variable is used internally by the parl binary loader to signal the child process that it's the child.

You should not rely on this variable outside of the PAR binary loader code. For a slightly more detailed discussion, please refer to the who_am_i.txt documentation file in the PAR source distribution which was contributed by Alan Stewart.

Documented only to avoid surprises if spawned applications expect to see a value initialized by the user.

👑 PAR_TEMP

Users should set "PAR_GLOBAL_TEMP" instead. "PAR_TEMP" is calculated from a variety of other variables. See the "NOTES" section in the pod for PAR.pm for a complete description of how the calculation proceeds. "PAR_TEMP", once calculated, is used as the location where PAR stores its extracted, temporary file cache.

🍓 PAR_TMPDIR

Contributes to the calculation of "PAR_TEMP", and is further explained there. Users should set "PAR_GLOBAL_TMPDIR" instead.

✨ PAR_VERBATIM

The "PAR_VERBATIM" variable controls the way Perl code is packaged into a PAR archive or binary executable. If it is set to a true value during the packaging process, modules (and scripts) are not passed through the default PAR::Filter::PodStrip filter which removes all POD documentation from the code. Note that the PAR::Filter::PatchContent filter is still applied.

The -F option to the pp tool overrides the "PAR_VERBATIM" setting. That means if you set PAR_VERBATIM=1 but specify -F PodStrip on the pp command line, the PodStrip filter will be applied.

"PAR_VERBATIM" is not used by the PAR application.

🌈 PAR_VERBOSE

Setting this environment variable to a positive integer has the same effect as using the -verbose switch to pp.

🦋 PP_OPTS

During a pp run, the contents of the "PP_OPTS" variable are treated as if they were part of the command line. In newer versions of PAR, you can also write options to a file and execute pp as follows to read the options from the file:

pp @FILENAME

That can, of course, be combined with other command line arguments to pp or the "PP_OPTS" variable.

💜 TMP, TEMP, TMPDIR, TEMPDIR

Please refer to "PAR_TMPDIR".

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🌟 SEE ALSO 🌟

• PAR, PAR::Tutorial
• par.pl, parl, pp
• PAR::Dist for details on PAR distributions.

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🫶 AUTHORS 🫶

Steffen Mueller <smueller@cpan.org>

You can write to the mailing list at <par@perl.org>, or send an empty mail to <par-subscribe@perl.org> to participate in the discussion. Archives of the mailing list are available at <https://www.mail-archive.com/par@perl.org/> or <https://groups.google.com/g/perl.par>.

Please submit bug reports to <https://github.com/rschupp/PAR/issues>. If you need support, however, joining the <par@perl.org> mailing list is preferred.

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💖 COPYRIGHT 💖

PAR: Copyright 2003-2010 by Audrey Tang, <cpan@audreyt.org>.

This document: Copyright 2006-2010 by Steffen Mueller, <smueller@cpan.org>

Some information has been taken from Alan Stewart's extra documentation in the contrib/ folder of the PAR distribution.

This program or documentation is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

See LICENSE.

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And that's the whole page bestie, no notes 💅 This little manual page came to you as perl v5.42.0, dated 2025-08-04 — and it ate, fr fr. Go forth and set your environment variables responsibly ✨🎀🦋