% perl -MAlien::Base::Wrapper=Alien::Foo,Alien::Bar -e cc -- -o foo.o -c foo.c % perl -MAlien::Base::Wrapper=Alien::Foo,Alien::Bar -e ld -- -o foo foo.o
From Makefile.PL (non-dynamic):
use ExtUtils::MakeMaker;
use Alien::Base::Wrapper qw( Alien::Foo Alien::Bar !export );
WriteMakefile(
'NAME' => 'Foo::XS',
'VERSION_FROM' => 'lib/Foo/XS.pm',
'CONFIGURE_REQUIRES => {
'ExtUtils::MakeMaker' => 6.52,
'Alien::Foo' => 0,
'Alien::Bar' => 0,
},
Alien::Base::Wrapper->mm_args,
);
From Makefile.PL (dynamic):
use Devel::CheckLib qw( check_lib );
use ExtUtils::MakeMaker 6.52;
my @mm_args;
my @libs;
if(check_lib( lib => [ 'foo' ] )
{
push @mm_args, LIBS => [ '-lfoo' ];
}
else
{
push @mm_args,
CC => '$(FULLPERL) -MAlien::Base::Wrapper=Alien::Foo -e cc --',
LD => '$(FULLPERL) -MAlien::Base::Wrapper=Alien::Foo -e ld --',
BUILD_REQUIRES => {
'Alien::Foo' => 0,
'Alien::Base::Wrapper' => 0,
}
;
}
WriteMakefile(
'NAME' => 'Foo::XS',
'VERSION_FROM' => 'lib/Foo/XS.pm',
'CONFIGURE_REQUIRES => {
'ExtUtils::MakeMaker' => 6.52,
},
@mm_args,
);
In the first example (from the command line), this class acts as a wrapper around the compiler and linker that Perl is configured to use. It takes the normal compiler and linker flags and adds the flags provided by the Aliens specified, and then executes the command. It will print the command to the console so that you can see exactly what is happening.
In the second example (from Makefile.PL non-dynamic), this class is used to generate the appropriate ExtUtils::MakeMaker (EUMM) arguments needed to "WriteMakefile".
In the third example (from Makefile.PL dynamic), we do a quick check to see if the simple linker flag "-lfoo" will work, if so we use that. If not, we use a wrapper around the compiler and linker that will use the alien flags that are known at build time. The problem that this form attempts to solve is that compiler and linker flags typically need to be determined at configure time, when a distribution is installed, meaning if you are going to use an Alien module then it needs to be a configure prerequisite, even if the library is already installed and easily detected on the operating system.
The author of this module believes that the third (from Makefile.PL dynamic) form is somewhat unnecessary. Alien modules based on Alien::Base have a few prerequisites, but they are well maintained and reliable, so while there is a small cost in terms of extra dependencies, the overall reliability thanks to reduced overall complexity.
% perl -MAlien::Base::Wrapper=Alien::Foo -e cc -- cflags
Invoke the C compiler with the appropriate flags from "Alien::Foo" and what is provided on the command line.
% perl -MAlien::Base::Wrapper=Alien::Foo -e ld -- ldflags
Invoke the linker with the appropriate flags from "Alien::Foo" and what is provided on the command line.
my %args = Alien::Base::Wrapper->mm_args;
Returns arguments that you can pass into "WriteMakefile" to compile/link against the specified Aliens.
my %args = Alien::Base::Wrapper->mb_args;
Returns arguments that you can pass into the constructor to Module::Build.
Contributors:
Diab Jerius (DJERIUS)
Roy Storey
Ilya Pavlov
David Mertens (run4flat)
Mark Nunberg (mordy, mnunberg)
Christian Walde (Mithaldu)
Brian Wightman (MidLifeXis)
Zaki Mughal (zmughal)
mohawk (mohawk2, ETJ)
Vikas N Kumar (vikasnkumar)
Flavio Poletti (polettix)
Salvador Fandiño (salva)
Gianni Ceccarelli (dakkar)
Pavel Shaydo (zwon, trinitum)
Kang-min Liu (劉康民, gugod)
Nicholas Shipp (nshp)
Juan Julián Merelo Guervós (JJ)
Joel Berger (JBERGER)
Petr Pisar (ppisar)
Lance Wicks (LANCEW)
Ahmad Fatoum (a3f, ATHREEF)
José Joaquín Atria (JJATRIA)
Duke Leto (LETO)
Shoichi Kaji (SKAJI)
Shawn Laffan (SLAFFAN)
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.