PAR(3) User Contributed Perl Documentation PAR(3)NAME
PAR - Perl Archive Toolkit
SYNOPSIS
(If you want to make an executable that contains all module, scripts
and data files, please consult the pp utility instead. pp used to be
part of the PAR distribution but is now shipped as part of the
PAR::Packer distribution instead.)
Following examples assume a foo.par file in Zip format.
To use Hello.pm from ./foo.par:
% perl -MPAR=./foo.par -MHello
% perl -MPAR=./foo -MHello # the .par part is optional
Same thing, but search foo.par in the @INC;
% perl -MPAR -Ifoo.par -MHello
% perl -MPAR -Ifoo -MHello # ditto
Following paths inside the PAR file are searched:
/lib/
/arch/
/i386-freebsd/ # i.e. $Config{archname}
/5.8.0/ # i.e. $Config{version}
/5.8.0/i386-freebsd/ # both of the above
/
PAR files may also (recursively) contain other PAR files. All files
under following paths will be considered as PAR files and searched as
well:
/par/i386-freebsd/ # i.e. $Config{archname}
/par/5.8.0/ # i.e. $Config{version}
/par/5.8.0/i386-freebsd/ # both of the above
/par/
Run script/test.pl or test.pl from foo.par:
% perl -MPAR foo.par test.pl # only when $0 ends in '.par'
However, if the .par archive contains either script/main.pl or main.pl,
then it is used instead:
% perl -MPAR foo.par test.pl # runs main.pl; @ARGV is 'test.pl'
Use in a program:
use PAR 'foo.par';
use Hello; # reads within foo.par
# PAR::read_file() returns a file inside any loaded PARs
my $conf = PAR::read_file('data/MyConfig.yaml');
# PAR::par_handle() returns an Archive::Zip handle
my $zip = PAR::par_handle('foo.par')
my $src = $zip->memberNamed('lib/Hello.pm')->contents;
You can also use wildcard characters:
use PAR '/home/foo/*.par'; # loads all PAR files in that directory
Since version 0.950, you can also use a different syntax for loading
.par archives:
use PAR { file => 'foo.par' }, { file => 'otherfile.par' };
Why? Because you can also do this:
use PAR { file => 'foo.par, fallback => 1 };
use Foo::Bar;
Foo::Bar will be searched in the system libs first and loaded from
foo.par if it wasn't found!
use PAR { file => 'foo.par', run => 'myscript' };
This will load foo.par as usual and then execute the script/myscript
file from the archive. Note that your program will not regain control.
When script/myscript exits, so does your main program. To make this
more useful, you can defer this to runtime: (otherwise equivalent)
require PAR;
PAR->import( { file => 'foo.par', run => 'myscript' } );
If you have PAR::Repository::Client installed, you can do this:
use PAR { repository => 'http://foo/bar/' };
use Module; # not locally installed!
And PAR will fetch any modules you don't have from the specified PAR
repository. For details on how this works, have a look at the SEE ALSO
section below. Instead of an URL or local path, you can construct an
PAR::Repository::Client object manually and pass that to PAR. If you
specify the "install => 1" option in the "use PAR" line above, the
distribution containing "Module" will be permanently installed on your
system. ("use PAR { repository => 'http://foo/bar', install => 1 };")
Furthermore, there is an "upgrade => 1" option that checks for upgrades
in the repository in addition to installing. Please note that an
upgraded version of a module is only loaded on the next run of your
application.
Adding the "dependencies => 1" option will enable
PAR::Repository::Client's static dependency resolution
(PAR::Repository::Client 0.23 and up).
Finally, you can combine the "run" and "repository" options to run an
application directly from a repository! (And you can add the "install"
option, too.)
use PAR { repository => 'http://foo/bar/', run => 'my_app' };
# Will not reach this point as we executed my_app,
DESCRIPTION
This module lets you use special zip files, called Perl Archives, as
libraries from which Perl modules can be loaded.
It supports loading XS modules by overriding DynaLoader bootstrapping
methods; it writes shared object file to a temporary file at the time
it is needed.
A .par file is mostly a zip of the blib/ directory after the build
process of a CPAN distribution. To generate a .par file yourself, all
you have to do is compress the modules under arch/ and lib/, e.g.:
% perl Makefile.PL
% make
% cd blib
% zip -r mymodule.par arch/ lib/
Afterward, you can just use mymodule.par anywhere in your @INC, use
PAR, and it will Just Work. Support for generating .par files is going
to be in the next (beyond 0.2805) release of Module::Build.
For convenience, you can set the "PERL5OPT" environment variable to
"-MPAR" to enable "PAR" processing globally (the overhead is small if
not used); setting it to "-MPAR=/path/to/mylib.par" will load a
specific PAR file. Alternatively, consider using the par.pl utility
bundled with the PAR::Packer distribution, or using the self-contained
parl utility which is also distributed with PAR::Packer on machines
without PAR.pm installed.
Note that self-containing scripts and executables created with par.pl
and pp may also be used as .par archives:
% pp -o packed.exe source.pl # generate packed.exe (see PAR::Packer)
% perl -MPAR=packed.exe other.pl # this also works
% perl -MPAR -Ipacked.exe other.pl # ditto
Please see "SYNOPSIS" for most typical use cases.
NOTES
Settings in META.yml packed inside the PAR file may affect PAR's
operation. For example, pp provides the "-C" ("--clean") option to
control the default behavior of temporary file creation.
Currently, pp-generated PAR files may attach four PAR-specific
attributes in META.yml:
par:
clean: 0 # default value of PAR_CLEAN
signature: '' # key ID of the SIGNATURE file
verbatim: 0 # was packed prerequisite's PODs preserved?
version: x.xx # PAR.pm version that generated this PAR
User-defined environment variables, like PAR_GLOBAL_CLEAN, always
overrides the ones set in META.yml. The algorithm for generating
caching/temporary directory is as follows:
· If PAR_GLOBAL_TEMP is specified, use it as the cache directory for
extracted libraries, and do not clean it up after execution.
· If PAR_GLOBAL_TEMP is not set, but PAR_CLEAN is specified, set
PAR_GLOBAL_TEMP to "TEMP/par-USER/temp-PID/", cleaning it after
execution.
· If both are not set, use "TEMP/par-USER/cache-HASH/" as the
PAR_GLOBAL_TEMP, reusing any existing files inside.
Here is a description of the variables the previous paths.
· TEMP is a temporary directory, which can be set via
$ENV{PAR_GLOBAL_TMPDIR}, $ENV{TMPDIR}, $ENV{TEMPDIR}, $ENV{TEMP} or
$ENV{TMP}, in that order of priority. If none of those are set,
C:\TEMP, /tmp are checked. If neither of them exists, . is used.
· USER is the user name, or SYSTEM if none can be found. On Win32,
this is $Win32::LoginName. On Unix, this is $ENV{USERNAME} or
$ENV{USER}.
· PID is the process ID. Forked children use the parent's PID.
· HASH is a crypto-hash of the entire par file or executable,
calculated at creation time. This value can be overloaded with
"pp"'s --tempdir parameter.
By default, PAR strips POD sections from bundled modules. In case that
causes trouble, you can turn this off by setting the environment
variable "PAR_VERBATIM" to 1.
import options
When you "use PAR {...}" or call PAR->import({...}), the following
options are available.
PAR->import({ file => 'foo.par' });
# or
PAR->import({ repository => 'http://foo/bar/' });
file
The par filename.
You must pass one option of either 'file' or 'repository'.
repository
A par repository (exclusive of file)
fallback
Search the system @INC before the par.
Off by default for loading .par files via "file =" ...>. On by
default for PAR repositories.
To prefer loading modules from a repository over the locally
installed modules, you can load the repository as follows:
use PAR { repository => 'http://foo/bar/', fallback => 0 };
run The name of a script to run in the par. Exits when done.
no_shlib_unpack
Skip unpacking bundled dynamic libraries from shlib/$archname. The
client may have them installed, or you may wish to cache them
yourself. In either case, they must end up in the standard install
location (such as /usr/local/lib/) or in $ENV{PAR_TEMP} before you
require the module which needs them. If they are not accessible
before you require the dependent module, perl will die with a
message such as "cannot open shared object file..."
SEE ALSO
The PAR homepage at <http://par.perl.org>.
PAR::Tutorial, PAR::FAQ (For a more current FAQ, refer to the
homepage.)
The PAR::Packer distribution which contains the packaging utilities:
par.pl, parl, pp.
PAR::Dist for details on PAR distributions.
PAR::Repository::Client for details on accessing PAR repositories.
PAR::Repository for details on how to set up such a repository.
Archive::Zip, "require" in perlfunc
ex::lib::zip, Acme::use::strict::with::pride
Steffen Mueller has detailed slides on using PAR for application
deployment at http://steffen-mueller.net/talks/appdeployment/
<http://steffen-mueller.net/talks/appdeployment/>.
PAR supports the prefork module. It declares various run-time
dependencies so you can use the prefork module to get streamlined
processes in a forking environment.
ACKNOWLEDGMENTS
Nicholas Clark for pointing out the mad source filter hook within the
(also mad) coderef @INC hook, as well as (even madder) tricks one can
play with PerlIO to avoid source filtering.
Ton Hospel for convincing me to ditch the "Filter::Simple"
implementation.
Uri Guttman for suggesting "read_file" and "par_handle" interfaces.
Antti Lankila for making me implement the self-contained executable
options via "par.pl -O".
See the AUTHORS file in the distribution for a list of people who have
sent helpful patches, ideas or comments.
AUTHORS
Audrey Tang <cpan@audreyt.org>
Steffen Mueller <smueller@cpan.org>
<http://par.perl.org/> is the official PAR website. 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.
Please submit bug reports to <bug-par@rt.cpan.org>. If you need
support, however, joining the <par@perl.org> mailing list is preferred.
COPYRIGHT
Copyright 2002-2010 by Audrey Tang <cpan@audreyt.org>. Copyright
2005-2010 by Steffen Mueller <smueller@cpan.org>
This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
See <http://www.perl.com/perl/misc/Artistic.html>
perl v5.16.2 2012-10-22 PAR(3)
