NAME
PkgConfig - Pure-Perl Core-Only replacement for pkg-config
SYNOPSIS
As a replacement for pkg-config
$ ppkg-config --libs --cflags --static gio-2.0
#outputs (lines artificially broken up for readability):
# -I/usr/include/glib-2.0 -I/usr/lib/glib-2.0/include
# -pthread -lgio-2.0 -lz -lresolv -lgobject-2.0
# -lgmodule-2.0 -ldl -lgthread-2.0 -pthread -lrt -lglib-2.0
pkg-config.pl
can be used as an alias for ppkg-config
on platforms that support it. It can also be installed as pkg-config
though this is not recommended if your system has a native pkg-config
.
Compare to: $ pkg-config --libs --cflags --static gio-2.0
#outputs ( "" ):
# -pthread -I/usr/include/glib-2.0 -I/usr/lib/glib-2.0/include
# -pthread -lgio-2.0 -lz -lresolv -lgobject-2.0 -lgmodule-2.0
# -ldl -lgthread-2.0 -lrt -lglib-2.0
From another Perl module
use PkgConfig;
my $o = PkgConfig->find('gio');
if($o->errmsg) {
#handle error
} else {
my $prefix = $o->get_var('prefix');
my @cflags = $o->get_cflags;
my @ldflags = $o->get_ldflags;
}
DESCRIPTION
PkgConfig
provides a pure-perl, core-only replacement for the pkg-config
utility.
This is not a description of the uses of pkg-config
but rather a description of the differences between the C version and the Perl one.
While pkg-config
is a compiled binary linked with glib, the pure-perl version has no such requirement, and will run wherever Perl ( >= 5.6 ) does.
The main supported options are the common --libs
, --cflags
, --static
, --exists
and --modversion
.
SCRIPT OPTIONS
USAGE
<packagename1 pkgname2..> [ --options ]
ARGUMENTS
By default, a library name must be supplied unless one of --version, or --real-version is specified.
The output should normally be suitable for passing to your favorite compiler.
--libs
(Also) print linker flags. Dependencies are traverse in order. Top-level dependencies will appear earlier in the command line than bottom-level dependencies.
--libs-only-L
Prints -L/-R part of "--libs". It defines library search path but without libraries to link with.
--libs-only-l
Prints the -l part of "--libs".
--libs-only-other
Prints the part of "--libs" not covered by "--libs-only-L" and "--libs-only-l", such as "--pthread".
--list-all
List all know packages.
--cflags
(Also) print compiler and C preprocessor flags.
--cflags-only-I
Prints the -I part of "--cflags"
--cflags-only-other
Prints the parts of "--cflags" not covered by "--cflags-only-I".
--modversion
Print the version of a given package.
--static
Use extra dependencies and libraries if linking against a static version of the requested library
--exists
Return success (0) if the package exists in the search path.
--with-path=PATH
Prepend PATH
to the list of search paths containing .pc
files.
This option can be specified multiple times with different paths, and they will all be added.
--env-only
Using this option, only paths specified in PKG_CONFIG_PATH
are recognized and any hard-coded defaults are ignored.
--guess-paths
Invoke gcc
and ld
to determine default linker and include paths. Default paths will be excluded from explicit -L and -I flags.
--define-variable=VARIABLE=VALUE
Define a variable, overriding any such variable definition in the .pc file, and allowing your value to interpolate with subsequent uses.
--variable=VARIABLE
This returns the value of a variable defined in a package's .pc file.
--print-variables
Print all defined variables found in the .pc files.
--version
The target version of pkg-config
emulated by this script
--real-version
The actual version of this script
--debug
Print debugging information
--silence-errors
Turn off errors. This is the default for non-libs/cflag/modversion arguments
--print-errors
Print errors to STDERR and takes precedence over --silence-errors
--short-errors
Ignored, but recognized for compatibility.
--errors-to-stdout
Print errors to STDOUT and takes precedence over --print-errors
ENVIRONMENT
the PKG_CONFIG_PATH
and PKG_CONFIG_LIBDIR
variables are honored and used as a colon-delimited (semicolon-delimited on Windows) list of directories with contain .pc
files.
Other environment variables recongized by both pkg-config
and PkgConfig include:
- PKG_CONFIG_ALLOW_SYSTEM_CFLAGS
- PKG_CONFIG_ALLOW_SYSTEM_LIBS
If Win32API::Registry is installed, on Windows (but not Cygwin) PkgConfig will also consult these registry keys. The names are ignored, but the values are paths containing .pc
files.
- HKEY_CURRENT_USER\Software\pkgconfig\PKG_CONFIG_PATH
- HKEY_LOCAL_MACHINE\Software\pkgconfig\PKG_CONFIG_PATH
Registry support should be considered somewhat experimental, subject to change in the future, though not without good reason. The rationale for this caveat is that this feature is documented in several places, but I have yet to find a working version that implements this feature.
MODULE OPTIONS
PkgConfig->find
my $result = PkgConfig->find($library, %options);
Find a library and return a result object. $library
can be either a single name of a library, or a reference to an array of library names
The options are in the form of hash keys and values, and the following are recognized:
search_path
search_path_override
-
Prepend search paths in addition to the paths specified in
$ENV{PKG_CONFIG_PATH}
The value is an array reference.the
_override
variant ignores defaults (likePKG_CONFIG_PATH
). file_path
-
Specifies the full path of the of the .pc file that you wish to load. It does not need to be in the search path (although any dependencies will need to be). Useful if you know the full path of the exact .pc file that you want.
exclude_cflags
exclude_ldflags
exclude_cflags_override
exclude_ldflags_override
-
Some
.pc
files specify default compiler and linker search paths, e.g.-I/usr/include -L/usr/lib
. Specifying them on the command line can be problematic as it drastically changes the search order.The above options will either append or replace the options which are excluded and filtered.
The default excluded linker and compiler options can be obtained via
@PkgConfig::DEFAULT_EXCLUDE_LFLAGS
and@PkgConfig::DEFAULT_EXCLUDE_CFLAGS
, respectively. static
-
Also specify static libraries.
no_recurse
-
Do not recurse dependencies. This is useful for just doing version checks.
VARS
-
Define a hashref of variables to override any variable definitions within the .pc files. This is equivalent to the
--define-variable
command-line option.
A PkgConfig
object is returned and may be queried about the results:
$o->errmsg
An error message, if any. This is a string and indicates an error.
$o->pkg_exists
Boolean value, true if the package exists.
$o->pkg_version
The version of the package
$o->get_cflags
$o->get_ldflags
Returns compiler and linker flags, respectively.
In list context, these methods return a list with each argument split on unescaped spaces.
In list context returns a list of compiler and linker flags, respectively.
In scalar context returns a string of compiler and linker flags with spaces and quotes escaped correctly.
$o->get_var($name)
Get the variable with the given name.
PkgConfig->Guess
This is a class method, and will replace the hard-coded default linker and include paths with those discovered by invoking ld(1) and cpp(1).
Currently this only works with GCC-supplied ld
and GNU ld
.
INSTALL
The Makefile.PL
that comes with PkgConfig
can take one or more --script
options to change of the name of the script or scripts that are installed.
- --script ppkg-config
-
This is the default and works on all platforms
- --script pkg-config.pl
-
This is installed by default on all platforms except for Windows, where the .pl may confuse the shell and cause the script to be opened in a text editor.
- --script pkg-config
-
This is the default name of the real
pkg-config
and so you have to specifically enable it if you want it. - --script none
-
Don't install any scripts.
Example, install all script names:
% perl Makefile.PL --script ppkg-config --script pkg-config.pl --script pkg-config
Example, don't install any scripts:
% perl Makefile.PL --script none
You can also set the environment variable PERL_PKG_CONFIG_SCRIPTS to the desired --script value (separating each script name with a comma ,
) to ensure that upgrades of PkgConfig do the same.
CAVEATS
On Strawberry Perl ppkg-config
acts like Strawberry is the system. This means that
The .pc files that are bundled with Strawberry are searched by default.
The Strawberry include and lib directories are used to compute the exclusion lists.
As of Strawberry 5.20.0.1 PkgConfig is bundled with Strawberry and pkg-config
is installed by default (in addition to ppkg-config
, though the ppkg-config
alias is NOT bundled with Strawberry itself).
For details on how to patch the .pc files bundled with older Strawberries, see the README.win32
that comes with this Distribution.
BUGS
The order of the flags is not exactly matching to that of pkg-config
. From my own observation, it seems this module does a better job, but I might be wrong.
Unlike pkg-config
, the scripts --exists
function will return nonzero if a package or any of its dependencies are missing. This differs from the behavior of pkg-config
which will just check for the definition of the package itself (without dependencies).
SEE ALSO
- pkg-config
-
The original C implementation
- pkgconf
-
An alternative C implementation
- PkgConfig::LibPkgConf
-
Perl bindings for
libpkgconf
, the same library thatpkgconf
is built on. - ExtUtils::PkgConfig
-
A wrapper around the
pkg-config
binary that can be used in yourMakefile.PL
orBuild.PL
. - http://www.openbsd.org/cgi-bin/cvsweb/src/usr.bin/pkg-config/
-
Another perl implementation of pkg-config
- pkg-config
-
Pure Ruby implementation.
- pykg-config
-
A Python implementation.
AUTHOR
Other contributors include:
- Vladimir Timofeev (vovkasm)
- kmx
- Sanel Zukan
- Breno G. de Oliveira (garu)
- Gregor Herrmann
- Ilya Pavlov (ILUX, Ilya33)
- Shawn Laffan (SLAFFAN, shawnlaffan)
- Ari Jolma (AJOLMA)
COPYRIGHT AND LICENSE
Copyright (C) 2012 M. Nunberg
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.