[perl5.git] / lib / ExtUtils / Embed.pm

# $Id: Embed.pm,v 1.22 1997/01/30 00:37:09 dougm Exp $
require 5.002;

package ExtUtils::Embed;
require Exporter;
require FileHandle;
use Config;
use Getopt::Std;

#Only when we need them
#require ExtUtils::MakeMaker;
#require ExtUtils::Liblist;

use vars qw(@ISA @EXPORT $VERSION
	    @Extensions $Verbose $lib_ext
	    $opt_o $opt_s 
	    );
use strict;

$VERSION = sprintf("%d.%02d", q$Revision: 1.22 $ =~ /(\d+)\.(\d+)/);
#for the namespace change
$Devel::embed::VERSION = "99.99";

sub Version { $VERSION; }

@ISA = qw(Exporter);
@EXPORT = qw(&xsinit &ldopts 
	     &ccopts &ccflags &ccdlflags &perl_inc
	     &xsi_header &xsi_protos &xsi_body);

#let's have Miniperl borrow from us instead
#require ExtUtils::Miniperl;
#*canon = \&ExtUtils::Miniperl::canon;

$Verbose = 0;
$lib_ext = $Config{lib_ext} || '.a';

sub xsinit { 
    my($file, $std, $mods) = @_;
    my($fh,@mods,%seen);
    $file ||= "perlxsi.c";

    if (@_) {
       @mods = @$mods if $mods;
    }
    else {
       getopts('o:s:');
       $file = $opt_o if defined $opt_o;
       $std  = $opt_s  if defined $opt_s;
       @mods = @ARGV;
    }
    $std = 1 unless scalar @mods;

    if ($file eq "STDOUT") {
	$fh = \*STDOUT;
    }
    else {
	$fh = new FileHandle "> $file";
    }

    push(@mods, static_ext()) if defined $std;
    @mods = grep(!$seen{$_}++, @mods);

    print $fh &xsi_header();
    print $fh "EXTERN_C void xs_init _((void));\n\n";     
    print $fh &xsi_protos(@mods);

    print $fh "\nEXTERN_C void\nxs_init()\n{\n";
    print $fh &xsi_body(@mods);
    print $fh "}\n";

}

sub xsi_header {
    return <<EOF;
#ifdef __cplusplus
extern "C" {
#endif

#include <EXTERN.h>
#include <perl.h>

#ifdef __cplusplus
}
#  ifndef EXTERN_C
#    define EXTERN_C extern "C"
#  endif
#else
#  ifndef EXTERN_C
#    define EXTERN_C extern
#  endif
#endif

EOF
}    

sub xsi_protos {
    my(@exts) = @_;
    my(@retval,%seen);

    foreach $_ (@exts){
        my($pname) = canon('/', $_);
        my($mname, $cname);
        ($mname = $pname) =~ s!/!::!g;
        ($cname = $pname) =~ s!/!__!g;
	my($ccode) = "EXTERN_C void boot_${cname} _((CV* cv));\n";
	next if $seen{$ccode}++;
        push(@retval, $ccode);
    }
    return join '', @retval;
}

sub xsi_body {
    my(@exts) = @_;
    my($pname,@retval,%seen);
    my($dl) = canon('/','DynaLoader');
    push(@retval, "\tdXSUB_SYS;\n") if $] > 5.002;
    push(@retval, "\tchar *file = __FILE__;\n\n");

    foreach $_ (@exts){
        my($pname) = canon('/', $_);
        my($mname, $cname, $ccode);
        ($mname = $pname) =~ s!/!::!g;
        ($cname = $pname) =~ s!/!__!g;
        if ($pname eq $dl){
            # Must NOT install 'DynaLoader::boot_DynaLoader' as 'bootstrap'!
            # boot_DynaLoader is called directly in DynaLoader.pm
            $ccode = "\t/* DynaLoader is a special case */\n\tnewXS(\"${mname}::boot_${cname}\", boot_${cname}, file);\n";
            push(@retval, $ccode) unless $seen{$ccode}++;
        } else {
            $ccode = "\tnewXS(\"${mname}::bootstrap\", boot_${cname}, file);\n";
            push(@retval, $ccode) unless $seen{$ccode}++;
        }
    }
    return join '', @retval;
}

sub static_ext {
    unless (scalar @Extensions) {
	@Extensions = sort split /\s+/, $Config{static_ext};
	unshift @Extensions, qw(DynaLoader);
    }
    @Extensions;
}

sub ldopts {
    require ExtUtils::MakeMaker;
    require ExtUtils::Liblist;
    my($std,$mods,$link_args,$path) = @_;
    my(@mods,@link_args,@argv);
    my($dllib,$config_libs,@potential_libs,@path);
    local($") = ' ' unless $" eq ' ';
    my $MM = bless {} => 'MY';
    if (scalar @_) {
       @link_args = @$link_args if $link_args;
       @mods = @$mods if $mods;
    }
    else {
       @argv = @ARGV;
       #hmm
       while($_ = shift @argv) {
	   /^-std$/  && do { $std = 1; next; };
	   /^--$/    && do { @link_args = @argv; last; };
	   /^-I(.*)/ && do { $path = $1 || shift @argv; next; };
	   push(@mods, $_); 
       }
    }
    $std = 1 unless scalar @link_args;
    @path = $path ? split(/:/, $path) : @INC;

    push(@potential_libs, @link_args)    if scalar @link_args;
    push(@potential_libs, $Config{libs}) if defined $std;

    push(@mods, static_ext()) if $std;

    my($mod,@ns,$root,$sub,$extra,$archive,@archives);
    print STDERR "Searching (@path) for archives\n" if $Verbose;
    foreach $mod (@mods) {
	@ns = split('::', $mod);
	$sub = $ns[-1];
	$root = $MM->catdir(@ns);
	
	print STDERR "searching for '$sub${lib_ext}'\n" if $Verbose;
	foreach (@path) {
	    next unless -e ($archive = $MM->catdir($_,"auto",$root,"$sub$lib_ext"));
	    push @archives, $archive;
	    if(-e ($extra = $MM->catdir($_,"auto",$root,"extralibs.ld"))) {
		local(*FH); 
		if(open(FH, $extra)) {
		    my($libs) = <FH>; chomp $libs;
		    push @potential_libs, split /\s+/, $libs;
		}
		else {  
		    warn "Couldn't open '$extra'"; 
		}
	    }
	    last;
	}
    }
    #print STDERR "\@potential_libs = @potential_libs\n";

    my($extralibs, $bsloadlibs, $ldloadlibs, $ld_run_path) =
	$MM->ext(join ' ', 
		 $MM->catdir("-L$Config{archlibexp}", "CORE"), " -lperl", 
		 @potential_libs);

    my $ld_or_bs = $bsloadlibs || $ldloadlibs;
    print STDERR "bs: $bsloadlibs ** ld: $ldloadlibs" if $Verbose;
    my $linkage = "$Config{ccdlflags} $Config{ldflags} @archives $ld_or_bs";
    print STDERR "ldopts: '$linkage'\n" if $Verbose;

    return $linkage if scalar @_;
    print "$linkage\n";
}

sub ccflags {
   print " $Config{ccflags} ";
}

sub ccdlflags {
   print " $Config{ccdlflags} ";
}

sub perl_inc {
   print " -I$Config{archlibexp}/CORE ";
}

sub ccopts {
   ccflags;
   perl_inc;
}

sub canon {
    my($as, @ext) = @_;
    foreach(@ext) {
       # might be X::Y or lib/auto/X/Y/Y.a
       next if s!::!/!g;
       s:^(lib|ext)/(auto/)?::;
       s:/\w+\.\w+$::;
    }
    grep(s:/:$as:, @ext) if ($as ne '/');
    @ext;
}

__END__

=head1 NAME

ExtUtils::Embed - Utilities for embedding Perl in C/C++ applications

=head1 SYNOPSIS


 perl -MExtUtils::Embed -e xsinit 
 perl -MExtUtils::Embed -e ldopts 

=head1 DESCRIPTION

ExtUtils::Embed provides utility functions for embedding a Perl interpreter
and extensions in your C/C++ applications.  
Typically, an application B<Makefile> will invoke ExtUtils::Embed
functions while building your application.  

=head1 @EXPORT

ExtUtils::Embed exports the following functions:

xsinit(), ldopts(), ccopts(), perl_inc(), ccflags(), 
ccdlflags(), xsi_header(), xsi_protos(), xsi_body()

=head1 FUNCTIONS

=item xsinit()

Generate C/C++ code for the XS initializer function.

When invoked as C<`perl -MExtUtils::Embed -e xsinit --`>
the following options are recognized:

B<-o> E<lt>output filenameE<gt> (Defaults to B<perlxsi.c>)

B<-o STDOUT> will print to STDOUT.

B<-std> (Write code for extensions that are linked with the current Perl.)

Any additional arguments are expected to be names of modules
to generate code for.

When invoked with parameters the following are accepted and optional:

C<xsinit($filename,$std,[@modules])>

Where,

B<$filename> is equivalent to the B<-o> option.

B<$std> is boolean, equivalent to the B<-std> option.  

B<[@modules]> is an array ref, same as additional arguments mentioned above.

=item Examples


 perl -MExtUtils::Embed -e xsinit -- -o xsinit.c Socket


This will generate code with an B<xs_init> function that glues the perl B<Socket::bootstrap> function 
to the C B<boot_Socket> function and writes it to a file named "xsinit.c".

Note that B<DynaLoader> is a special case where it must call B<boot_DynaLoader> directly.

 perl -MExtUtils::Embed -e xsinit


This will generate code for linking with B<DynaLoader> and 
each static extension found in B<$Config{static_ext}>.
The code is written to the default file name B<perlxsi.c>.


 perl -MExtUtils::Embed -e xsinit -- -o xsinit.c -std DBI DBD::Oracle


Here, code is written for all the currently linked extensions along with code
for B<DBI> and B<DBD::Oracle>.

If you have a working B<DynaLoader> then there is rarely any need to statically link in any 
other extensions.

=item ldopts()

Output arguments for linking the Perl library and extensions to your
application.

When invoked as C<`perl -MExtUtils::Embed -e ldopts --`>
the following options are recognized:

B<-std> 

Output arguments for linking the Perl library and any extensions linked
with the current Perl.

B<-I> E<lt>path1:path2E<gt>

Search path for ModuleName.a archives.  
Default path is B<@INC>.
Library archives are expected to be found as 
B</some/path/auto/ModuleName/ModuleName.a>
For example, when looking for B<Socket.a> relative to a search path, 
we should find B<auto/Socket/Socket.a>  

When looking for B<DBD::Oracle> relative to a search path,
we should find B<auto/DBD/Oracle/Oracle.a>

Keep in mind, you can always supply B</my/own/path/ModuleName.a>
as an additional linker argument.

B<-->  E<lt>list of linker argsE<gt>

Additional linker arguments to be considered.

Any additional arguments found before the B<--> token 
are expected to be names of modules to generate code for.

When invoked with parameters the following are accepted and optional:

C<ldopts($std,[@modules],[@link_args],$path)>

Where,

B<$std> is boolean, equivalent to the B<-std> option.  

B<[@modules]> is equivalent to additional arguments found before the B<--> token.

B<[@link_args]> is equivalent to arguments found after the B<--> token.

B<$path> is equivalent to the B<-I> option.

In addition, when ldopts is called with parameters, it will return the argument string
rather than print it to STDOUT.

=item Examples


 perl -MExtUtils::Embed -e ldopts


This will print arguments for linking with B<libperl.a>, B<DynaLoader> and 
extensions found in B<$Config{static_ext}>.  This includes libraries
found in B<$Config{libs}> and the first ModuleName.a library
for each extension that is found by searching B<@INC> or the path 
specifed by the B<-I> option.  
In addition, when ModuleName.a is found, additional linker arguments
are picked up from the B<extralibs.ld> file in the same directory.


 perl -MExtUtils::Embed -e ldopts -- -std Socket


This will do the same as the above example, along with printing additional arguments for linking with the B<Socket> extension.


 perl -MExtUtils::Embed -e ldopts -- DynaLoader


This will print arguments for linking with just the B<DynaLoader> extension
and B<libperl.a>.


 perl -MExtUtils::Embed -e ldopts -- -std Msql -- -L/usr/msql/lib -lmsql


Any arguments after the second '--' token are additional linker
arguments that will be examined for potential conflict.  If there is no
conflict, the additional arguments will be part of the output.  


=item perl_inc()

For including perl header files this function simply prints:

 -I$Config{archlibexp}/CORE  

So, rather than having to say:

 perl -MConfig -e 'print "-I$Config{archlibexp}/CORE"'

Just say:

 perl -MExtUtils::Embed -e perl_inc

=item ccflags(), ccdlflags()

These functions simply print $Config{ccflags} and $Config{ccdlflags}

=item ccopts()

This function combines perl_inc(), ccflags() and ccdlflags() into one.

=item xsi_header()

This function simply returns a string defining the same B<EXTERN_C> macro as
B<perlmain.c> along with #including B<perl.h> and B<EXTERN.h>.  

=item xsi_protos(@modules)

This function returns a string of B<boot_$ModuleName> prototypes for each @modules.

=item xsi_body(@modules)

This function returns a string of calls to B<newXS()> that glue the module B<bootstrap>
function to B<boot_ModuleName> for each @modules.

B<xsinit()> uses the xsi_* functions to generate most of it's code.

=head1 EXAMPLES

For examples on how to use B<ExtUtils::Embed> for building C/C++ applications
with embedded perl, see the eg/ directory and L<perlembed>.

=head1 SEE ALSO

L<perlembed>

=head1 AUTHOR

Doug MacEachern E<lt>F<dougm@osf.org>E<gt>

Based on ideas from Tim Bunce E<lt>F<Tim.Bunce@ig.co.uk>E<gt> and
B<minimod.pl> by Andreas Koenig E<lt>F<k@anna.in-berlin.de>E<gt> and Tim Bunce.

=cut
Commit	Line	Data
f86702cc	1	# $Id: Embed.pm,v 1.22 1997/01/30 00:37:09 dougm Exp $
a2c6f8f1	2	require 5.002;
	3
	4	package ExtUtils::Embed;
	5	require Exporter;
	6	require FileHandle;
	7	use Config;
	8	use Getopt::Std;
	9
	10	#Only when we need them
	11	#require ExtUtils::MakeMaker;
	12	#require ExtUtils::Liblist;
	13
	14	use vars qw(@ISA @EXPORT $VERSION
	15	@Extensions $Verbose $lib_ext
	16	$opt_o $opt_s
	17	);
	18	use strict;
	19
f86702cc	20	$VERSION = sprintf("%d.%02d", q$Revision: 1.22 $ =~ /(\d+)\.(\d+)/);
a2c6f8f1	21	#for the namespace change
	22	$Devel::embed::VERSION = "99.99";
	23
	24	sub Version { $VERSION; }
	25
	26	@ISA = qw(Exporter);
	27	@EXPORT = qw(&xsinit &ldopts
	28	&ccopts &ccflags &ccdlflags &perl_inc
	29	&xsi_header &xsi_protos &xsi_body);
	30
	31	#let's have Miniperl borrow from us instead
	32	#require ExtUtils::Miniperl;
	33	#*canon = \&ExtUtils::Miniperl::canon;
	34
	35	$Verbose = 0;
	36	$lib_ext = $Config{lib_ext} \|\| '.a';
	37
	38	sub xsinit {
	39	my($file, $std, $mods) = @_;
	40	my($fh,@mods,%seen);
	41	$file \|\|= "perlxsi.c";
	42
	43	if (@_) {
	44	@mods = @$mods if $mods;
	45	}
	46	else {
	47	getopts('o:s:');
	48	$file = $opt_o if defined $opt_o;
	49	$std = $opt_s if defined $opt_s;
	50	@mods = @ARGV;
	51	}
	52	$std = 1 unless scalar @mods;
	53
	54	if ($file eq "STDOUT") {
	55	$fh = \*STDOUT;
	56	}
	57	else {
	58	$fh = new FileHandle "> $file";
	59	}
	60
	61	push(@mods, static_ext()) if defined $std;
	62	@mods = grep(!$seen{$_}++, @mods);
	63
	64	print $fh &xsi_header();
	65	print $fh "EXTERN_C void xs_init _((void));\n\n";
	66	print $fh &xsi_protos(@mods);
	67
	68	print $fh "\nEXTERN_C void\nxs_init()\n{\n";
	69	print $fh &xsi_body(@mods);
	70	print $fh "}\n";
	71
	72	}
	73
	74	sub xsi_header {
	75	return <<EOF;
	76	#ifdef __cplusplus
	77	extern "C" {
	78	#endif
	79
	80	#include <EXTERN.h>
	81	#include <perl.h>
	82
	83	#ifdef __cplusplus
	84	}
85	# ifndef EXTERN_C
86	# define EXTERN_C extern "C"
87	# endif
88	#else
89	# ifndef EXTERN_C
90	# define EXTERN_C extern
91	# endif
92	#endif
93
94	EOF
95	}
96
97	sub xsi_protos {
98	my(@exts) = @_;
99	my(@retval,%seen);
100
101	foreach $_ (@exts){
102	my($pname) = canon('/', $_);
103	my($mname, $cname);
104	($mname = $pname) =~ s!/!::!g;
105	($cname = $pname) =~ s!/!__!g;
106	my($ccode) = "EXTERN_C void boot_${cname} _((CV* cv));\n";
107	next if $seen{$ccode}++;
108	push(@retval, $ccode);
109	}
110	return join '', @retval;
111	}
112
113	sub xsi_body {
114	my(@exts) = @_;
115	my($pname,@retval,%seen);
116	my($dl) = canon('/','DynaLoader');
117	push(@retval, "\tdXSUB_SYS;\n") if $] > 5.002;
118	push(@retval, "\tchar *file = __FILE__;\n\n");
119
120	foreach $_ (@exts){
121	my($pname) = canon('/', $_);
122	my($mname, $cname, $ccode);
123	($mname = $pname) =~ s!/!::!g;
124	($cname = $pname) =~ s!/!__!g;
125	if ($pname eq $dl){
126	# Must NOT install 'DynaLoader::boot_DynaLoader' as 'bootstrap'!
127	# boot_DynaLoader is called directly in DynaLoader.pm
128	$ccode = "\t/* DynaLoader is a special case */\n\tnewXS(\"${mname}::boot_${cname}\", boot_${cname}, file);\n";
129	push(@retval, $ccode) unless $seen{$ccode}++;
130	} else {
131	$ccode = "\tnewXS(\"${mname}::bootstrap\", boot_${cname}, file);\n";
132	push(@retval, $ccode) unless $seen{$ccode}++;
133	}
134	}
135	return join '', @retval;
136	}
137
138	sub static_ext {
139	unless (scalar @Extensions) {
140	@Extensions = sort split /\s+/, $Config{static_ext};
141	unshift @Extensions, qw(DynaLoader);
142	}
143	@Extensions;
144	}
145
146	sub ldopts {
147	require ExtUtils::MakeMaker;
148	require ExtUtils::Liblist;
149	my($std,$mods,$link_args,$path) = @_;
150	my(@mods,@link_args,@argv);
151	my($dllib,$config_libs,@potential_libs,@path);
152	local($") = ' ' unless $" eq ' ';
153	my $MM = bless {} => 'MY';
154	if (scalar @_) {
155	@link_args = @$link_args if $link_args;
156	@mods = @$mods if $mods;
157	}
158	else {
159	@argv = @ARGV;
160	#hmm
161	while($_ = shift @argv) {
162	/^-std$/ && do { $std = 1; next; };
163	/^--$/ && do { @link_args = @argv; last; };
164	/^-I(.*)/ && do { $path = $1 \|\| shift @argv; next; };
165	push(@mods, $_);
166	}
167	}
168	$std = 1 unless scalar @link_args;
169	@path = $path ? split(/:/, $path) : @INC;
170
171	push(@potential_libs, @link_args) if scalar @link_args;
172	push(@potential_libs, $Config{libs}) if defined $std;
173
174	push(@mods, static_ext()) if $std;
175
176	my($mod,@ns,$root,$sub,$extra,$archive,@archives);
177	print STDERR "Searching (@path) for archives\n" if $Verbose;
178	foreach $mod (@mods) {
179	@ns = split('::', $mod);
180	$sub = $ns[-1];
181	$root = $MM->catdir(@ns);
182
183	print STDERR "searching for '$sub${lib_ext}'\n" if $Verbose;
184	foreach (@path) {
185	next unless -e ($archive = $MM->catdir($_,"auto",$root,"$sub$lib_ext"));
186	push @archives, $archive;
187	if(-e ($extra = $MM->catdir($_,"auto",$root,"extralibs.ld"))) {
188	local(*FH);
189	if(open(FH, $extra)) {
190	my($libs) = <FH>; chomp $libs;
191	push @potential_libs, split /\s+/, $libs;
192	}
193	else {
194	warn "Couldn't open '$extra'";
195	}
196	}
197	last;
198	}
199	}
200	#print STDERR "\@potential_libs = @potential_libs\n";
201
202	my($extralibs, $bsloadlibs, $ldloadlibs, $ld_run_path) =
203	$MM->ext(join ' ',
36477c24	204	$MM->catdir("-L$Config{archlibexp}", "CORE"), " -lperl",
a2c6f8f1	205	@potential_libs);
	206
	207	my $ld_or_bs = $bsloadlibs \|\| $ldloadlibs;
	208	print STDERR "bs: $bsloadlibs ** ld: $ldloadlibs" if $Verbose;
f86702cc	209	my $linkage = "$Config{ccdlflags} $Config{ldflags} @archives $ld_or_bs";
a2c6f8f1	210	print STDERR "ldopts: '$linkage'\n" if $Verbose;
	211
	212	return $linkage if scalar @_;
	213	print "$linkage\n";
	214	}
	215
	216	sub ccflags {
	217	print " $Config{ccflags} ";
	218	}
	219
	220	sub ccdlflags {
	221	print " $Config{ccdlflags} ";
	222	}
	223
	224	sub perl_inc {
ff68c719	225	print " -I$Config{archlibexp}/CORE ";
a2c6f8f1	226	}
	227
	228	sub ccopts {
	229	ccflags;
a2c6f8f1	230	perl_inc;
	231	}
	232
	233	sub canon {
	234	my($as, @ext) = @_;
	235	foreach(@ext) {
	236	# might be X::Y or lib/auto/X/Y/Y.a
	237	next if s!::!/!g;
	238	s:^(lib\|ext)/(auto/)?::;
	239	s:/\w+\.\w+$::;
	240	}
	241	grep(s:/:$as:, @ext) if ($as ne '/');
	242	@ext;
	243	}
	244
	245	__END__
	246
	247	=head1 NAME
	248
	249	ExtUtils::Embed - Utilities for embedding Perl in C/C++ applications
	250
	251	=head1 SYNOPSIS
	252
	253
	254	perl -MExtUtils::Embed -e xsinit
	255	perl -MExtUtils::Embed -e ldopts
	256
	257	=head1 DESCRIPTION
	258
	259	ExtUtils::Embed provides utility functions for embedding a Perl interpreter
	260	and extensions in your C/C++ applications.
	261	Typically, an application B<Makefile> will invoke ExtUtils::Embed
	262	functions while building your application.
	263
	264	=head1 @EXPORT
	265
	266	ExtUtils::Embed exports the following functions:
a6006777	267
4e864201 JM	268	xsinit(), ldopts(), ccopts(), perl_inc(), ccflags(),
4e864201 JM	269	ccdlflags(), xsi_header(), xsi_protos(), xsi_body()
a2c6f8f1	270
	271	=head1 FUNCTIONS
	272
	273	=item xsinit()
	274
4e864201	275	Generate C/C++ code for the XS initializer function.
a2c6f8f1	276
	277	When invoked as C<`perl -MExtUtils::Embed -e xsinit --`>
	278	the following options are recognized:
	279
4e864201	280	B<-o> E<lt>output filenameE<gt> (Defaults to B<perlxsi.c>)
a2c6f8f1	281
	282	B<-o STDOUT> will print to STDOUT.
	283
	284	B<-std> (Write code for extensions that are linked with the current Perl.)
	285
	286	Any additional arguments are expected to be names of modules
	287	to generate code for.
	288
	289	When invoked with parameters the following are accepted and optional:
	290
	291	C<xsinit($filename,$std,[@modules])>
	292
	293	Where,
	294
	295	B<$filename> is equivalent to the B<-o> option.
	296
	297	B<$std> is boolean, equivalent to the B<-std> option.
	298
	299	B<[@modules]> is an array ref, same as additional arguments mentioned above.
	300
	301	=item Examples
	302
a6006777	303
a2c6f8f1	304	perl -MExtUtils::Embed -e xsinit -- -o xsinit.c Socket
	305
	306
	307	This will generate code with an B<xs_init> function that glues the perl B<Socket::bootstrap> function
	308	to the C B<boot_Socket> function and writes it to a file named "xsinit.c".
	309
	310	Note that B<DynaLoader> is a special case where it must call B<boot_DynaLoader> directly.
	311
	312	perl -MExtUtils::Embed -e xsinit
	313
	314
	315	This will generate code for linking with B<DynaLoader> and
	316	each static extension found in B<$Config{static_ext}>.
	317	The code is written to the default file name B<perlxsi.c>.
	318
	319
	320	perl -MExtUtils::Embed -e xsinit -- -o xsinit.c -std DBI DBD::Oracle
	321
	322
	323	Here, code is written for all the currently linked extensions along with code
	324	for B<DBI> and B<DBD::Oracle>.
	325
	326	If you have a working B<DynaLoader> then there is rarely any need to statically link in any
	327	other extensions.
	328
	329	=item ldopts()
	330
	331	Output arguments for linking the Perl library and extensions to your
	332	application.
	333
	334	When invoked as C<`perl -MExtUtils::Embed -e ldopts --`>
	335	the following options are recognized:
	336
	337	B<-std>
	338
	339	Output arguments for linking the Perl library and any extensions linked
	340	with the current Perl.
	341
4e864201	342	B<-I> E<lt>path1:path2E<gt>
a2c6f8f1	343
	344	Search path for ModuleName.a archives.
	345	Default path is B<@INC>.
	346	Library archives are expected to be found as
	347	B</some/path/auto/ModuleName/ModuleName.a>
	348	For example, when looking for B<Socket.a> relative to a search path,
	349	we should find B<auto/Socket/Socket.a>
	350
	351	When looking for B<DBD::Oracle> relative to a search path,
	352	we should find B<auto/DBD/Oracle/Oracle.a>
	353
	354	Keep in mind, you can always supply B</my/own/path/ModuleName.a>
	355	as an additional linker argument.
	356
4e864201	357	B<--> E<lt>list of linker argsE<gt>
a2c6f8f1	358
	359	Additional linker arguments to be considered.
	360
	361	Any additional arguments found before the B<--> token
	362	are expected to be names of modules to generate code for.
	363
	364	When invoked with parameters the following are accepted and optional:
	365
	366	C<ldopts($std,[@modules],[@link_args],$path)>
	367
	368	Where,
	369
	370	B<$std> is boolean, equivalent to the B<-std> option.
	371
	372	B<[@modules]> is equivalent to additional arguments found before the B<--> token.
	373
	374	B<[@link_args]> is equivalent to arguments found after the B<--> token.
	375
	376	B<$path> is equivalent to the B<-I> option.
	377
	378	In addition, when ldopts is called with parameters, it will return the argument string
	379	rather than print it to STDOUT.
	380
	381	=item Examples
	382
	383
	384	perl -MExtUtils::Embed -e ldopts
	385
	386
	387	This will print arguments for linking with B<libperl.a>, B<DynaLoader> and
	388	extensions found in B<$Config{static_ext}>. This includes libraries
	389	found in B<$Config{libs}> and the first ModuleName.a library
	390	for each extension that is found by searching B<@INC> or the path
	391	specifed by the B<-I> option.
	392	In addition, when ModuleName.a is found, additional linker arguments
	393	are picked up from the B<extralibs.ld> file in the same directory.
	394
	395
	396	perl -MExtUtils::Embed -e ldopts -- -std Socket
a6006777	397
a2c6f8f1	398
	399	This will do the same as the above example, along with printing additional arguments for linking with the B<Socket> extension.
	400
	401
	402	perl -MExtUtils::Embed -e ldopts -- DynaLoader
	403
	404
	405	This will print arguments for linking with just the B<DynaLoader> extension
	406	and B<libperl.a>.
	407
	408
	409	perl -MExtUtils::Embed -e ldopts -- -std Msql -- -L/usr/msql/lib -lmsql
	410
	411
	412	Any arguments after the second '--' token are additional linker
	413	arguments that will be examined for potential conflict. If there is no
	414	conflict, the additional arguments will be part of the output.
	415
	416
	417	=item perl_inc()
	418
	419	For including perl header files this function simply prints:
	420
36477c24	421	-I$Config{archlibexp}/CORE
a2c6f8f1	422
	423	So, rather than having to say:
	424
36477c24	425	perl -MConfig -e 'print "-I$Config{archlibexp}/CORE"'
a2c6f8f1	426
	427	Just say:
	428
	429	perl -MExtUtils::Embed -e perl_inc
	430
	431	=item ccflags(), ccdlflags()
	432
	433	These functions simply print $Config{ccflags} and $Config{ccdlflags}
	434
	435	=item ccopts()
	436
	437	This function combines perl_inc(), ccflags() and ccdlflags() into one.
	438
	439	=item xsi_header()
	440
	441	This function simply returns a string defining the same B<EXTERN_C> macro as
	442	B<perlmain.c> along with #including B<perl.h> and B<EXTERN.h>.
	443
	444	=item xsi_protos(@modules)
	445
	446	This function returns a string of B<boot_$ModuleName> prototypes for each @modules.
	447
	448	=item xsi_body(@modules)
	449
	450	This function returns a string of calls to B<newXS()> that glue the module B<bootstrap>
	451	function to B<boot_ModuleName> for each @modules.
	452
	453	B<xsinit()> uses the xsi_* functions to generate most of it's code.
	454
	455	=head1 EXAMPLES
	456
	457	For examples on how to use B<ExtUtils::Embed> for building C/C++ applications
4e864201	458	with embedded perl, see the eg/ directory and L<perlembed>.
a6006777	459
a2c6f8f1	460	=head1 SEE ALSO
a2c6f8f1	461
4e864201	462	L<perlembed>
a2c6f8f1	463
	464	=head1 AUTHOR
	465
4e864201	466	Doug MacEachern E<lt>F<dougm@osf.org>E<gt>
a2c6f8f1	467
4e864201 JM	468	Based on ideas from Tim Bunce E<lt>F<Tim.Bunce@ig.co.uk>E<gt> and
4e864201 JM	469	B<minimod.pl> by Andreas Koenig E<lt>F<k@anna.in-berlin.de>E<gt> and Tim Bunce.
a2c6f8f1	470
	471	=cut
	472