[p5sagit/p5-mst-13.2.git] / lib / ExtUtils / Mksymlists.pm

package ExtUtils::Mksymlists;

use 5.006_001;
use strict qw[ subs refs ];
# no strict 'vars';  # until filehandles are exempted

use Carp;
use Exporter;
use Config;
our(@ISA, @EXPORT, $VERSION);
@ISA = 'Exporter';
@EXPORT = '&Mksymlists';
$VERSION = 1.18_00;

sub Mksymlists {
    my(%spec) = @_;
    my($osname) = $^O;

    croak("Insufficient information specified to Mksymlists")
        unless ( $spec{NAME} or
                 ($spec{FILE} and ($spec{DL_FUNCS} or $spec{FUNCLIST})) );

    $spec{DL_VARS} = [] unless $spec{DL_VARS};
    ($spec{FILE} = $spec{NAME}) =~ s/.*::// unless $spec{FILE};
    $spec{FUNCLIST} = [] unless $spec{FUNCLIST};
    $spec{DL_FUNCS} = { $spec{NAME} => [] }
        unless ( ($spec{DL_FUNCS} and keys %{$spec{DL_FUNCS}}) or
                 @{$spec{FUNCLIST}});
    if (defined $spec{DL_FUNCS}) {
        my($package);
        foreach $package (keys %{$spec{DL_FUNCS}}) {
            my($packprefix,$sym,$bootseen);
            ($packprefix = $package) =~ s/\W/_/g;
            foreach $sym (@{$spec{DL_FUNCS}->{$package}}) {
                if ($sym =~ /^boot_/) {
                    push(@{$spec{FUNCLIST}},$sym);
                    $bootseen++;
                }
                else { push(@{$spec{FUNCLIST}},"XS_${packprefix}_$sym"); }
            }
            push(@{$spec{FUNCLIST}},"boot_$packprefix") unless $bootseen;
        }
    }

#    We'll need this if we ever add any OS which uses mod2fname
#    not as pseudo-builtin.
#    require DynaLoader;
    if (defined &DynaLoader::mod2fname and not $spec{DLBASE}) {
        $spec{DLBASE} = DynaLoader::mod2fname([ split(/::/,$spec{NAME}) ]);
    }

    if    ($osname eq 'aix') { _write_aix(\%spec); }
    elsif ($osname eq 'MacOS'){ _write_aix(\%spec) }
    elsif ($osname eq 'VMS') { _write_vms(\%spec) }
    elsif ($osname eq 'os2') { _write_os2(\%spec) }
    elsif ($osname eq 'MSWin32') { _write_win32(\%spec) }
    else { croak("Don't know how to create linker option file for $osname\n"); }
}


sub _write_aix {
    my($data) = @_;

    rename "$data->{FILE}.exp", "$data->{FILE}.exp_old";

    open(EXP,">$data->{FILE}.exp")
        or croak("Can't create $data->{FILE}.exp: $!\n");
    print EXP join("\n",@{$data->{DL_VARS}}, "\n") if @{$data->{DL_VARS}};
    print EXP join("\n",@{$data->{FUNCLIST}}, "\n") if @{$data->{FUNCLIST}};
    close EXP;
}


sub _write_os2 {
    my($data) = @_;
    require Config;
    my $threaded = ($Config::Config{archname} =~ /-thread/ ? " threaded" : "");

    if (not $data->{DLBASE}) {
        ($data->{DLBASE} = $data->{NAME}) =~ s/.*:://;
        $data->{DLBASE} = substr($data->{DLBASE},0,7) . '_';
    }
    my $distname = $data->{DISTNAME} || $data->{NAME};
    $distname = "Distribution $distname";
    my $patchlevel = $Config{perl_patchlevel} || '';
    $patchlevel = " pl$patchlevel" if $patchlevel;
    my $comment = <<EOC;
Perl (v$Config::Config{version}$threaded$patchlevel) module $data->{NAME}
EOC
    chomp $comment;
    if ($data->{INSTALLDIRS} and $data->{INSTALLDIRS} eq 'perl') {
	$distname = 'perl5-porters@perl.org';
	$comment = "Core $comment";
    }
    $comment = "$comment (Perl-config: $Config{config_args})";
    $comment = substr($comment, 0, 200) . "...)" if length $comment > 203;
    rename "$data->{FILE}.def", "$data->{FILE}_def.old";

    open(DEF,">$data->{FILE}.def")
        or croak("Can't create $data->{FILE}.def: $!\n");
    print DEF "LIBRARY '$data->{DLBASE}' INITINSTANCE TERMINSTANCE\n";
    print DEF "DESCRIPTION '\@#$distname:$data->{VERSION}#\@ $comment'\n";
    print DEF "CODE LOADONCALL\n";
    print DEF "DATA LOADONCALL NONSHARED MULTIPLE\n";
    print DEF "EXPORTS\n  ";
    print DEF join("\n  ",@{$data->{DL_VARS}}, "\n") if @{$data->{DL_VARS}};
    print DEF join("\n  ",@{$data->{FUNCLIST}}, "\n") if @{$data->{FUNCLIST}};
    if (%{$data->{IMPORTS}}) {
        print DEF "IMPORTS\n";
	my ($name, $exp);
	while (($name, $exp)= each %{$data->{IMPORTS}}) {
	    print DEF "  $name=$exp\n";
	}
    }
    close DEF;
}

sub _write_win32 {
    my($data) = @_;

    require Config;
    if (not $data->{DLBASE}) {
        ($data->{DLBASE} = $data->{NAME}) =~ s/.*:://;
        $data->{DLBASE} = substr($data->{DLBASE},0,7) . '_';
    }
    rename "$data->{FILE}.def", "$data->{FILE}_def.old";

    open(DEF,">$data->{FILE}.def")
        or croak("Can't create $data->{FILE}.def: $!\n");
    # put library name in quotes (it could be a keyword, like 'Alias')
    if ($Config::Config{'cc'} !~ /^gcc/i) {
      print DEF "LIBRARY \"$data->{DLBASE}\"\n";
    }
    print DEF "EXPORTS\n  ";
    my @syms;
    # Export public symbols both with and without underscores to
    # ensure compatibility between DLLs from different compilers
    # NOTE: DynaLoader itself only uses the names without underscores,
    # so this is only to cover the case when the extension DLL may be
    # linked to directly from C. GSAR 97-07-10
    if ($Config::Config{'cc'} =~ /^bcc/i) {
	for (@{$data->{DL_VARS}}, @{$data->{FUNCLIST}}) {
	    push @syms, "_$_", "$_ = _$_";
	}
    }
    else {
	for (@{$data->{DL_VARS}}, @{$data->{FUNCLIST}}) {
	    push @syms, "$_", "_$_ = $_";
	}
    }
    print DEF join("\n  ",@syms, "\n") if @syms;
    if (%{$data->{IMPORTS}}) {
        print DEF "IMPORTS\n";
        my ($name, $exp);
        while (($name, $exp)= each %{$data->{IMPORTS}}) {
            print DEF "  $name=$exp\n";
        }
    }
    close DEF;
}


sub _write_vms {
    my($data) = @_;

    require Config; # a reminder for once we do $^O
    require ExtUtils::XSSymSet;

    my($isvax) = $Config::Config{'archname'} =~ /VAX/i;
    my($set) = new ExtUtils::XSSymSet;
    my($sym);

    rename "$data->{FILE}.opt", "$data->{FILE}.opt_old";

    open(OPT,">$data->{FILE}.opt")
        or croak("Can't create $data->{FILE}.opt: $!\n");

    # Options file declaring universal symbols
    # Used when linking shareable image for dynamic extension,
    # or when linking PerlShr into which we've added this package
    # as a static extension
    # We don't do anything to preserve order, so we won't relax
    # the GSMATCH criteria for a dynamic extension

    print OPT "case_sensitive=yes\n"
        if $Config::Config{d_vms_case_sensitive_symbols};
    foreach $sym (@{$data->{FUNCLIST}}) {
        my $safe = $set->addsym($sym);
        if ($isvax) { print OPT "UNIVERSAL=$safe\n" }
        else        { print OPT "SYMBOL_VECTOR=($safe=PROCEDURE)\n"; }
    }
    foreach $sym (@{$data->{DL_VARS}}) {
        my $safe = $set->addsym($sym);
        print OPT "PSECT_ATTR=${sym},PIC,OVR,RD,NOEXE,WRT,NOSHR\n";
        if ($isvax) { print OPT "UNIVERSAL=$safe\n" }
        else        { print OPT "SYMBOL_VECTOR=($safe=DATA)\n"; }
    }
    close OPT;

}

1;

__END__

=head1 NAME

ExtUtils::Mksymlists - write linker options files for dynamic extension

=head1 SYNOPSIS

    use ExtUtils::Mksymlists;
    Mksymlists({ NAME     => $name ,
                 DL_VARS  => [ $var1, $var2, $var3 ],
                 DL_FUNCS => { $pkg1 => [ $func1, $func2 ],
                               $pkg2 => [ $func3 ] });

=head1 DESCRIPTION

C<ExtUtils::Mksymlists> produces files used by the linker under some OSs
during the creation of shared libraries for dynamic extensions.  It is
normally called from a MakeMaker-generated Makefile when the extension
is built.  The linker option file is generated by calling the function
C<Mksymlists>, which is exported by default from C<ExtUtils::Mksymlists>.
It takes one argument, a list of key-value pairs, in which the following
keys are recognized:

=over 4

=item DLBASE

This item specifies the name by which the linker knows the
extension, which may be different from the name of the
extension itself (for instance, some linkers add an '_' to the
name of the extension).  If it is not specified, it is derived
from the NAME attribute.  It is presently used only by OS2 and Win32.

=item DL_FUNCS

This is identical to the DL_FUNCS attribute available via MakeMaker,
from which it is usually taken.  Its value is a reference to an
associative array, in which each key is the name of a package, and
each value is an a reference to an array of function names which
should be exported by the extension.  For instance, one might say
C<DL_FUNCS =E<gt> { Homer::Iliad =E<gt> [ qw(trojans greeks) ],
Homer::Odyssey =E<gt> [ qw(travellers family suitors) ] }>.  The
function names should be identical to those in the XSUB code;
C<Mksymlists> will alter the names written to the linker option
file to match the changes made by F<xsubpp>.  In addition, if
none of the functions in a list begin with the string B<boot_>,
C<Mksymlists> will add a bootstrap function for that package,
just as xsubpp does.  (If a B<boot_E<lt>pkgE<gt>> function is
present in the list, it is passed through unchanged.)  If
DL_FUNCS is not specified, it defaults to the bootstrap
function for the extension specified in NAME.

=item DL_VARS

This is identical to the DL_VARS attribute available via MakeMaker,
and, like DL_FUNCS, it is usually specified via MakeMaker.  Its
value is a reference to an array of variable names which should
be exported by the extension.

=item FILE

This key can be used to specify the name of the linker option file
(minus the OS-specific extension), if for some reason you do not
want to use the default value, which is the last word of the NAME
attribute (I<e.g.> for C<Tk::Canvas>, FILE defaults to C<Canvas>).

=item FUNCLIST

This provides an alternate means to specify function names to be
exported from the extension.  Its value is a reference to an
array of function names to be exported by the extension.  These
names are passed through unaltered to the linker options file.
Specifying a value for the FUNCLIST attribute suppresses automatic
generation of the bootstrap function for the package. To still create
the bootstrap name you have to specify the package name in the
DL_FUNCS hash:

    Mksymlists({ NAME     => $name ,
		 FUNCLIST => [ $func1, $func2 ],
                 DL_FUNCS => { $pkg => [] } });


=item IMPORTS

This attribute is used to specify names to be imported into the
extension. It is currently only used by OS/2 and Win32.

=item NAME

This gives the name of the extension (I<e.g.> C<Tk::Canvas>) for which
the linker option file will be produced.

=back

When calling C<Mksymlists>, one should always specify the NAME
attribute.  In most cases, this is all that's necessary.  In
the case of unusual extensions, however, the other attributes
can be used to provide additional information to the linker.

=head1 AUTHOR

Charles Bailey I<E<lt>bailey@newman.upenn.eduE<gt>>

=head1 REVISION

Last revised 14-Feb-1996, for Perl 5.002.
Commit	Line	Data
c07a80fd	1	package ExtUtils::Mksymlists;
cb50131a	2
3b825e41	3	use 5.006_001;
c07a80fd	4	use strict qw[ subs refs ];
	5	# no strict 'vars'; # until filehandles are exempted
	6
	7	use Carp;
c07a80fd	8	use Exporter;
1102eebe	9	use Config;
cb50131a	10	our(@ISA, @EXPORT, $VERSION);
f1387719	11	@ISA = 'Exporter';
f1387719	12	@EXPORT = '&Mksymlists';
39234879	13	$VERSION = 1.18_00;
c07a80fd	14
	15	sub Mksymlists {
	16	my(%spec) = @_;
f1387719	17	my($osname) = $^O;
c07a80fd	18
	19	croak("Insufficient information specified to Mksymlists")
	20	unless ( $spec{NAME} or
	21	($spec{FILE} and ($spec{DL_FUNCS} or $spec{FUNCLIST})) );
	22
	23	$spec{DL_VARS} = [] unless $spec{DL_VARS};
	24	($spec{FILE} = $spec{NAME}) =~ s/.*::// unless $spec{FILE};
348844dc	25	$spec{FUNCLIST} = [] unless $spec{FUNCLIST};
c07a80fd	26	$spec{DL_FUNCS} = { $spec{NAME} => [] }
c07a80fd	27	unless ( ($spec{DL_FUNCS} and keys %{$spec{DL_FUNCS}}) or
348844dc	28	@{$spec{FUNCLIST}});
c07a80fd	29	if (defined $spec{DL_FUNCS}) {
	30	my($package);
	31	foreach $package (keys %{$spec{DL_FUNCS}}) {
	32	my($packprefix,$sym,$bootseen);
	33	($packprefix = $package) =~ s/\W/_/g;
	34	foreach $sym (@{$spec{DL_FUNCS}->{$package}}) {
	35	if ($sym =~ /^boot_/) {
	36	push(@{$spec{FUNCLIST}},$sym);
	37	$bootseen++;
	38	}
	39	else { push(@{$spec{FUNCLIST}},"XS_${packprefix}_$sym"); }
	40	}
	41	push(@{$spec{FUNCLIST}},"boot_$packprefix") unless $bootseen;
	42	}
	43	}
	44
	45	# We'll need this if we ever add any OS which uses mod2fname
760ac839	46	# not as pseudo-builtin.
c07a80fd	47	# require DynaLoader;
c2e89b3d	48	if (defined &DynaLoader::mod2fname and not $spec{DLBASE}) {
	49	$spec{DLBASE} = DynaLoader::mod2fname([ split(/::/,$spec{NAME}) ]);
	50	}
c07a80fd	51
f1387719	52	if ($osname eq 'aix') { _write_aix(\%spec); }
6d697788	53	elsif ($osname eq 'MacOS'){ _write_aix(\%spec) }
f1387719	54	elsif ($osname eq 'VMS') { _write_vms(\%spec) }
bab2b58e	55	elsif ($osname eq 'os2') { _write_os2(\%spec) }
68dc0745	56	elsif ($osname eq 'MSWin32') { _write_win32(\%spec) }
f1387719	57	else { croak("Don't know how to create linker option file for $osname\n"); }
c07a80fd	58	}
	59
	60
	61	sub _write_aix {
	62	my($data) = @_;
	63
	64	rename "$data->{FILE}.exp", "$data->{FILE}.exp_old";
	65
	66	open(EXP,">$data->{FILE}.exp")
	67	or croak("Can't create $data->{FILE}.exp: $!\n");
	68	print EXP join("\n",@{$data->{DL_VARS}}, "\n") if @{$data->{DL_VARS}};
	69	print EXP join("\n",@{$data->{FUNCLIST}}, "\n") if @{$data->{FUNCLIST}};
	70	close EXP;
	71	}
	72
	73
	74	sub _write_os2 {
	75	my($data) = @_;
6ee623d5	76	require Config;
6ee623d5	77	my $threaded = ($Config::Config{archname} =~ /-thread/ ? " threaded" : "");
c07a80fd	78
	79	if (not $data->{DLBASE}) {
	80	($data->{DLBASE} = $data->{NAME}) =~ s/.*:://;
	81	$data->{DLBASE} = substr($data->{DLBASE},0,7) . '_';
	82	}
3cfae81b	83	my $distname = $data->{DISTNAME} \|\| $data->{NAME};
3cfae81b	84	$distname = "Distribution $distname";
52e4c282	85	my $patchlevel = $Config{perl_patchlevel} \|\| '';
	86	$patchlevel = " pl$patchlevel" if $patchlevel;
	87	my $comment = <<EOC;
	88	Perl (v$Config::Config{version}$threaded$patchlevel) module $data->{NAME}
	89	EOC
	90	chomp $comment;
3cfae81b	91	if ($data->{INSTALLDIRS} and $data->{INSTALLDIRS} eq 'perl') {
	92	$distname = 'perl5-porters@perl.org';
	93	$comment = "Core $comment";
	94	}
1102eebe	95	$comment = "$comment (Perl-config: $Config{config_args})";
1102eebe	96	$comment = substr($comment, 0, 200) . "...)" if length $comment > 203;
c07a80fd	97	rename "$data->{FILE}.def", "$data->{FILE}_def.old";
	98
	99	open(DEF,">$data->{FILE}.def")
	100	or croak("Can't create $data->{FILE}.def: $!\n");
	101	print DEF "LIBRARY '$data->{DLBASE}' INITINSTANCE TERMINSTANCE\n";
3cfae81b	102	print DEF "DESCRIPTION '\@#$distname:$data->{VERSION}#\@ $comment'\n";
c07a80fd	103	print DEF "CODE LOADONCALL\n";
c07a80fd	104	print DEF "DATA LOADONCALL NONSHARED MULTIPLE\n";
c2e89b3d	105	print DEF "EXPORTS\n ";
	106	print DEF join("\n ",@{$data->{DL_VARS}}, "\n") if @{$data->{DL_VARS}};
	107	print DEF join("\n ",@{$data->{FUNCLIST}}, "\n") if @{$data->{FUNCLIST}};
	108	if (%{$data->{IMPORTS}}) {
	109	print DEF "IMPORTS\n";
875fa795	110	my ($name, $exp);
	111	while (($name, $exp)= each %{$data->{IMPORTS}}) {
	112	print DEF " $name=$exp\n";
	113	}
c2e89b3d	114	}
c07a80fd	115	close DEF;
	116	}
	117
68dc0745	118	sub _write_win32 {
	119	my($data) = @_;
	120
3e3baf6d	121	require Config;
68dc0745	122	if (not $data->{DLBASE}) {
	123	($data->{DLBASE} = $data->{NAME}) =~ s/.*:://;
	124	$data->{DLBASE} = substr($data->{DLBASE},0,7) . '_';
	125	}
	126	rename "$data->{FILE}.def", "$data->{FILE}_def.old";
	127
	128	open(DEF,">$data->{FILE}.def")
	129	or croak("Can't create $data->{FILE}.def: $!\n");
84902520	130	# put library name in quotes (it could be a keyword, like 'Alias')
5b0d9cbe	131	if ($Config::Config{'cc'} !~ /^gcc/i) {
5b0d9cbe	132	print DEF "LIBRARY \"$data->{DLBASE}\"\n";
5b0d9cbe	133	}
68dc0745	134	print DEF "EXPORTS\n ";
84902520	135	my @syms;
	136	# Export public symbols both with and without underscores to
	137	# ensure compatibility between DLLs from different compilers
	138	# NOTE: DynaLoader itself only uses the names without underscores,
	139	# so this is only to cover the case when the extension DLL may be
	140	# linked to directly from C. GSAR 97-07-10
3e3baf6d	141	if ($Config::Config{'cc'} =~ /^bcc/i) {
84902520	142	for (@{$data->{DL_VARS}}, @{$data->{FUNCLIST}}) {
	143	push @syms, "_$_", "$_ = _$_";
	144	}
3e3baf6d	145	}
84902520	146	else {
	147	for (@{$data->{DL_VARS}}, @{$data->{FUNCLIST}}) {
	148	push @syms, "$_", "_$_ = $_";
	149	}
	150	}
	151	print DEF join("\n ",@syms, "\n") if @syms;
68dc0745	152	if (%{$data->{IMPORTS}}) {
	153	print DEF "IMPORTS\n";
	154	my ($name, $exp);
	155	while (($name, $exp)= each %{$data->{IMPORTS}}) {
	156	print DEF " $name=$exp\n";
	157	}
	158	}
	159	close DEF;
	160	}
	161
c07a80fd	162
	163	sub _write_vms {
	164	my($data) = @_;
a6e61155	165
f1387719	166	require Config; # a reminder for once we do $^O
ff0cee69	167	require ExtUtils::XSSymSet;
a6e61155	168
8c99d73e	169	my($isvax) = $Config::Config{'archname'} =~ /VAX/i;
ff0cee69	170	my($set) = new ExtUtils::XSSymSet;
c07a80fd	171	my($sym);
	172
	173	rename "$data->{FILE}.opt", "$data->{FILE}.opt_old";
	174
	175	open(OPT,">$data->{FILE}.opt")
	176	or croak("Can't create $data->{FILE}.opt: $!\n");
	177
	178	# Options file declaring universal symbols
	179	# Used when linking shareable image for dynamic extension,
	180	# or when linking PerlShr into which we've added this package
	181	# as a static extension
	182	# We don't do anything to preserve order, so we won't relax
	183	# the GSMATCH criteria for a dynamic extension
	184
80601f72	185	print OPT "case_sensitive=yes\n"
80601f72	186	if $Config::Config{d_vms_case_sensitive_symbols};
c07a80fd	187	foreach $sym (@{$data->{FUNCLIST}}) {
ff0cee69	188	my $safe = $set->addsym($sym);
	189	if ($isvax) { print OPT "UNIVERSAL=$safe\n" }
	190	else { print OPT "SYMBOL_VECTOR=($safe=PROCEDURE)\n"; }
c07a80fd	191	}
c07a80fd	192	foreach $sym (@{$data->{DL_VARS}}) {
ff0cee69	193	my $safe = $set->addsym($sym);
c07a80fd	194	print OPT "PSECT_ATTR=${sym},PIC,OVR,RD,NOEXE,WRT,NOSHR\n";
ff0cee69	195	if ($isvax) { print OPT "UNIVERSAL=$safe\n" }
ff0cee69	196	else { print OPT "SYMBOL_VECTOR=($safe=DATA)\n"; }
c07a80fd	197	}
	198	close OPT;
	199
c07a80fd	200	}
	201
	202	1;
	203
	204	__END__
	205
	206	=head1 NAME
	207
	208	ExtUtils::Mksymlists - write linker options files for dynamic extension
	209
	210	=head1 SYNOPSIS
	211
	212	use ExtUtils::Mksymlists;
	213	Mksymlists({ NAME => $name ,
	214	DL_VARS => [ $var1, $var2, $var3 ],
	215	DL_FUNCS => { $pkg1 => [ $func1, $func2 ],
	216	$pkg2 => [ $func3 ] });
	217
	218	=head1 DESCRIPTION
	219
	220	C<ExtUtils::Mksymlists> produces files used by the linker under some OSs
1fef88e7	221	during the creation of shared libraries for dynamic extensions. It is
c07a80fd	222	normally called from a MakeMaker-generated Makefile when the extension
	223	is built. The linker option file is generated by calling the function
	224	C<Mksymlists>, which is exported by default from C<ExtUtils::Mksymlists>.
	225	It takes one argument, a list of key-value pairs, in which the following
	226	keys are recognized:
	227
bbc7dcd2	228	=over 4
2ae324a7	229
875fa795	230	=item DLBASE
c07a80fd	231
875fa795	232	This item specifies the name by which the linker knows the
	233	extension, which may be different from the name of the
	234	extension itself (for instance, some linkers add an '_' to the
	235	name of the extension). If it is not specified, it is derived
	236	from the NAME attribute. It is presently used only by OS2 and Win32.
c07a80fd	237
	238	=item DL_FUNCS
	239
	240	This is identical to the DL_FUNCS attribute available via MakeMaker,
	241	from which it is usually taken. Its value is a reference to an
	242	associative array, in which each key is the name of a package, and
	243	each value is an a reference to an array of function names which
	244	should be exported by the extension. For instance, one might say
875fa795	245	C<DL_FUNCS =E<gt> { Homer::Iliad =E<gt> [ qw(trojans greeks) ],
a5f75d66	246	Homer::Odyssey =E<gt> [ qw(travellers family suitors) ] }>. The
c07a80fd	247	function names should be identical to those in the XSUB code;
	248	C<Mksymlists> will alter the names written to the linker option
	249	file to match the changes made by F<xsubpp>. In addition, if
	250	none of the functions in a list begin with the string B<boot_>,
	251	C<Mksymlists> will add a bootstrap function for that package,
	252	just as xsubpp does. (If a B<boot_E<lt>pkgE<gt>> function is
	253	present in the list, it is passed through unchanged.) If
	254	DL_FUNCS is not specified, it defaults to the bootstrap
	255	function for the extension specified in NAME.
	256
	257	=item DL_VARS
	258
	259	This is identical to the DL_VARS attribute available via MakeMaker,
	260	and, like DL_FUNCS, it is usually specified via MakeMaker. Its
	261	value is a reference to an array of variable names which should
	262	be exported by the extension.
	263
	264	=item FILE
	265
	266	This key can be used to specify the name of the linker option file
	267	(minus the OS-specific extension), if for some reason you do not
	268	want to use the default value, which is the last word of the NAME
875fa795	269	attribute (I<e.g.> for C<Tk::Canvas>, FILE defaults to C<Canvas>).
c07a80fd	270
	271	=item FUNCLIST
	272
	273	This provides an alternate means to specify function names to be
	274	exported from the extension. Its value is a reference to an
	275	array of function names to be exported by the extension. These
	276	names are passed through unaltered to the linker options file.
de592821	277	Specifying a value for the FUNCLIST attribute suppresses automatic
875fa795	278	generation of the bootstrap function for the package. To still create
	279	the bootstrap name you have to specify the package name in the
	280	DL_FUNCS hash:
c07a80fd	281
875fa795	282	Mksymlists({ NAME => $name ,
	283	FUNCLIST => [ $func1, $func2 ],
	284	DL_FUNCS => { $pkg => [] } });
c07a80fd	285
875fa795	286
	287	=item IMPORTS
	288
	289	This attribute is used to specify names to be imported into the
	290	extension. It is currently only used by OS/2 and Win32.
	291
	292	=item NAME
	293
	294	This gives the name of the extension (I<e.g.> C<Tk::Canvas>) for which
	295	the linker option file will be produced.
c07a80fd	296
2ae324a7	297	=back
2ae324a7	298
c07a80fd	299	When calling C<Mksymlists>, one should always specify the NAME
	300	attribute. In most cases, this is all that's necessary. In
	301	the case of unusual extensions, however, the other attributes
	302	can be used to provide additional information to the linker.
	303
	304	=head1 AUTHOR
	305
bd3fa61c	306	Charles Bailey I<E<lt>bailey@newman.upenn.eduE<gt>>
c07a80fd	307
	308	=head1 REVISION
	309
a5f75d66	310	Last revised 14-Feb-1996, for Perl 5.002.