find_lib

my(@libs) = find_lib(%args);

This will return a list of dynamic libraries, or empty list if none were found.

[version 0.05]

If called in scalar context it will return the first library found.

Arguments are key value pairs with these keys:

lib

Must be either a string with the name of a single library or a reference to an array of strings of library names. Depending on your platform, "CheckLib" will prepend "lib" or append ".dll" or ".so" when searching.

[version 0.11]

As a special case, if "*" is specified then any libs found will match.

libpath

A string or array of additional paths to search for libraries.

systempath

[version 0.11]

A string or array of system paths to search for instead of letting FFI::CheckLib determine the system path. You can set this to "[]" in order to not search any system paths.

symbol

A string or a list of symbol names that must be found.

verify

A code reference used to verify a library really is the one that you want. It should take two arguments, which is the name of the library and the full path to the library pathname. It should return true if it is acceptable, and false otherwise. You can use this in conjunction with FFI::Platypus to determine if it is going to meet your needs. Example:

use FFI::CheckLib;
use FFI::Platypus;

my($lib) = find_lib(
  lib => 'foo',
  verify => sub {
    my($name, $libpath) = @_;

    my $ffi = FFI::Platypus->new;
    $ffi->lib($libpath);

    my $f = $ffi->function('foo_version', [] => 'int');

    return $f->call() >= 500; # we accept version 500 or better
  },
);

recursive

[version 0.11]

Recursively search for libraries in any non-system paths (those provided via "libpath" above).

try_linker_script

[version 0.24]

Some vendors provide ".so" files that are linker scripts that point to the real binary shared library. These linker scripts can be used by gcc or clang, but are not directly usable by FFI::Platypus and friends. On select platforms, this options will use the linker command ("ld") to attempt to resolve the real ".so" for non-binary files. Since there is extra overhead this is off by default.

An example is libyaml on Red Hat based Linux distributions. On Debian these are handled with symlinks and no trickery is required.

alien

[version 0.25]

If no libraries can be found, try the given aliens instead. The Alien classes specified must provide the Alien::Base interface for dynamic libraries, which is to say they should provide a method called "dynamic_libs" that returns a list of dynamic libraries.

[version 0.28]

In 0.28 and later, if the Alien is not installed then it will be ignored and this module will search in system or specified directories only. This module will still throw an exception, if the Alien doesn't look like a module name or if it does not provide a "dynamic_libs" method (which is implemented by all Alien::Base subclasses).

[version 0.30] [breaking change]

Starting with version 0.30, libraries provided by Aliens is preferred over the system libraries. The original thinking was that you want to prefer the system libraries because they are more likely to get patched with regular system updates. Unfortunately, the reason a module needs to install an Alien is likely because the system library is not new enough, so we now prefer the Aliens instead.

assert_lib

assert_lib(%args);

This behaves exactly the same as find_lib, except that instead of returning empty list of failure it throws an exception.

check_lib_or_exit

check_lib_or_exit(%args);

This behaves exactly the same as assert_lib, except that instead of dying, it warns (with exactly the same error message) and exists. This is intended for use in "Makefile.PL" or "Build.PL"

find_lib_or_exit

[version 0.05]

my(@libs) = find_lib_or_exit(%args);

This behaves exactly the same as find_lib, except that if the library is not found, it will call exit with an appropriate diagnostic.

find_lib_or_die

[version 0.06]

my(@libs) = find_lib_or_die(%args);

This behaves exactly the same as find_lib, except that if the library is not found, it will die with an appropriate diagnostic.

check_lib

my $bool = check_lib(%args);

This behaves exactly the same as find_lib, except that it returns true (1) on finding the appropriate libraries or false (0) otherwise.

which

[version 0.17]

my $path = which($name);

Return the path to the first library that matches the given name.

Not exported by default.

where

[version 0.17]

my @paths = where($name);

Return the paths to all the libraries that match the given name.

Not exported by default.

has_symbols

[version 0.17]

my $bool = has_symbols($path, @symbol_names);

Returns true if all of the symbols can be found in the dynamic library located at the given path. Can be useful in conjunction with "verify" with "find_lib" above.

Not exported by default.

system_path

[version 0.20]

my $path = FFI::CheckLib::system_path;

Returns the system path as a list reference. On some systems, this is "PATH" on others it might be "LD_LIBRARY_PATH" on still others it could be something completely different. So although you may add items to this list, you should probably do some careful consideration before you do so.

This function is not exportable, even on request.