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# Generated from XSLoader.pm.PL (resolved %Config::Config value)
package XSLoader;
# And Gandalf said: 'Many folk like to know beforehand what is to
# be set on the table; but those who have laboured to prepare the
# feast like to keep their secret; for wonder makes the words of
# praise louder.'
# (Quote from Tolkien sugested by Anno Siegel.)
#
# See pod text at end of file for documentation.
# See also ext/DynaLoader/README in source tree for other information.
#
# Tim.Bunce@ig.co.uk, August 1994
$VERSION = "0.01"; # avoid typo warning
# enable debug/trace messages from DynaLoader perl code
# $dl_debug = $ENV{PERL_DL_DEBUG} || 0 unless defined $dl_debug;
my $dl_dlext = 'dll';
package DynaLoader;
# No prizes for guessing why we don't say 'bootstrap DynaLoader;' here.
# NOTE: All dl_*.xs (including dl_none.xs) define a dl_error() XSUB
boot_DynaLoader('DynaLoader') if defined(&boot_DynaLoader) &&
!defined(&dl_error);
package XSLoader;
1; # End of main code
# The bootstrap function cannot be autoloaded (without complications)
# so we define it here:
sub load {
package DynaLoader;
my($module) = $_[0];
# work with static linking too
my $b = "$module\::bootstrap";
goto &$b if defined &$b;
goto retry unless $module and defined &dl_load_file;
my @modparts = split(/::/,$module);
my $modfname = $modparts[-1];
my $modpname = join('/',@modparts);
my $modlibname = (caller())[1];
my $c = @modparts;
$modlibname =~ s,[\\/][^\\/]+$,, while $c--; # Q&D basename
my $file = "$modlibname/auto/$modpname/$modfname.$dl_dlext";
# print STDERR "XSLoader::load for $module ($file)\n" if $dl_debug;
my $bs = $file;
$bs =~ s/(\.\w+)?(;\d*)?$/\.bs/; # look for .bs 'beside' the library
goto retry if not -f $file or -s $bs;
my $bootname = "boot_$module";
$bootname =~ s/\W/_/g;
@dl_require_symbols = ($bootname);
my $boot_symbol_ref;
if ($^O eq 'darwin') {
if ($boot_symbol_ref = dl_find_symbol(0, $bootname)) {
goto boot; #extension library has already been loaded, e.g. darwin
}
}
# Many dynamic extension loading problems will appear to come from
# this section of code: XYZ failed at line 123 of DynaLoader.pm.
# Often these errors are actually occurring in the initialisation
# C code of the extension XS file. Perl reports the error as being
# in this perl code simply because this was the last perl code
# it executed.
my $libref = dl_load_file($file, 0) or do {
require Carp;
Carp::croak("Can't load '$file' for module $module: " . dl_error());
};
push(@dl_librefs,$libref); # record loaded object
my @unresolved = dl_undef_symbols();
if (@unresolved) {
require Carp;
Carp::carp("Undefined symbols present after loading $file: @unresolved\n");
}
$boot_symbol_ref = dl_find_symbol($libref, $bootname) or do {
require Carp;
Carp::croak("Can't find '$bootname' symbol in $file\n");
};
push(@dl_modules, $module); # record loaded module
boot:
my $xs = dl_install_xsub("${module}::bootstrap", $boot_symbol_ref, $file);
# See comment block above
return &$xs(@_);
retry:
require DynaLoader;
goto &DynaLoader::bootstrap_inherit;
}
__END__
=head1 NAME
XSLoader - Dynamically load C libraries into Perl code
=head1 SYNOPSIS
package YourPackage;
use XSLoader;
XSLoader::load 'YourPackage', @args;
=head1 DESCRIPTION
This module defines a standard I<simplified> interface to the dynamic
linking mechanisms available on many platforms. Its primary purpose is
to implement cheap automatic dynamic loading of Perl modules.
For more complicated interface see L<DynaLoader>.
=head1 AUTHOR
Ilya Zakharevich: extraction from DynaLoader.
=cut
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