


H2XS(1)          Perl Programmers Reference Guide         H2XS(1)


NAME
       h2xs - convert .h C header files to Perl extensions

SYNOPSIS
       h2xs [-ACOPXcdf] [-v version] [-n module_name] [-p prefix]
       [-s sub] [headerfile ... [extra_libraries]]

       h2xs -h

DESCRIPTION
       h2xs builds a Perl extension from C header files.  The
       extension will include functions which can be used to
       retrieve the value of any #define statement which was in
       the C header files.

       The module_name will be used for the name of the exten-
       sion.  If module_name is not supplied then the name of the
       first header file will be used, with the first character
       capitalized.

       If the extension might need extra libraries, they should
       be included here.  The extension Makefile.PL will take
       care of checking whether the libraries actually exist and
       how they should be loaded.  The extra libraries should be
       specified in the form -lm -lposix, etc, just as on the cc
       command line.  By default, the Makefile.PL will search
       through the library path determined by Configure.  That
       path can be augmented by including arguments of the form
       -L/another/library/path in the extra-libraries argument.

OPTIONS
       -A   Omit all autoload facilities.  This is the same as -c
            but also removes the `use AutoLoader' statement from
            the .pm file.

       -C   Omits creation of the Changes file, and adds a HIS-
            TORY section to the POD template.

       -F   Additional flags to specify to C preprocessor when
            scanning header for function declarations.  Should
            not be used without -x.

       -M regular expression
            selects functions/macros to process.

       -O   Allows a pre-existing extension directory to be over-
            written.

       -P   Omit the autogenerated stub POD section.

       -X   Omit the XS portion.  Used to generate templates for
            a module which is not XS-based.  `-c' and `-f' are
            implicitly enabled.




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       -a   Generate an accessor method for each element of
            structs and unions. The generated methods are named
            after the element name; will return the current value
            of the element if called without additional argu-
            ments; and will set the element to the supplied value
            (and return the new value) if called with an addi-
            tional argument. Embedded structures and unions are
            returned as a pointer rather than the complete struc-
            ture, to facilitate chained calls.

            These methods all apply to the Ptr type for the
            structure; additionally two methods are constructed
            for the structure type itself, `_to_ptr' which
            returns a Ptr type pointing to the same structure,
            and a `new' method to construct and return a new
            structure, initialised to zeroes.

       -c   Omit `constant()' from the .xs file and corresponding
            specialised `AUTOLOAD' from the .pm file.

       -d   Turn on debugging messages.

       -f   Allows an extension to be created for a header even
            if that header is not found in standard include
            directories.

       -h   Print the usage, help and version for this h2xs and
            exit.

       -k   For function arguments declared as `const', omit the
            const attribute in the generated XS code.

       -m   Experimental: for each variable declared in the
            header file(s), declare a perl variable of the same
            name magically tied to the C variable.

       -n module_name
            Specifies a name to be used for the extension, e.g.,
            -n RPC::DCE

       -o regular expression
            Use "opaque" data type for the C types matched by the
            regular expression, even if these types are `type-
            def'-equivalent to types from typemaps.  Should not
            be used without -x.

            This may be useful since, say, types which are `type-
            def'-equivalent to integers may represent OS-related
            handles, and one may want to work with these handles
            in OO-way, as in `$handle->do_something()'.  Use `-o
            .' if you want to handle all the `typedef'ed types as
            opaque types.

            The type-to-match is whitewashed (except for commas,



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            which have no whitespace before them, and multiple
            `*' which have no whitespace between them).

       -p prefix
            Specify a prefix which should be removed from the
            Perl function names, e.g., -p sec_rgy_ This sets up
            the XS PREFIX keyword and removes the prefix from
            functions that are autoloaded via the `constant()'
            mechanism.

       -s sub1,sub2
            Create a perl subroutine for the specified macros
            rather than autoload with the constant() subroutine.
            These macros are assumed to have a return type of
            char *, e.g., -s sec_rgy_wildcard_name,sec_rgy_wild-
            card_sid.

       -v version
            Specify a version number for this extension.  This
            version number is added to the templates.  The
            default is 0.01.

       -x   Automatically generate XSUBs basing on function dec-
            larations in the header file.  The package `C::Scan'
            should be installed. If this option is specified, the
            name of the header file may look like `NAME1,NAME2'.
            In this case NAME1 is used instead of the specified
            string, but XSUBs are emitted only for the declara-
            tions included from file NAME2.

            Note that some types of arguments/return-values for
            functions may result in XSUB-declarations/typemap-
            entries which need hand-editing. Such may be objects
            which cannot be converted from/to a pointer (like
            `long long'), pointers to functions, or arrays.  See
            also the section on the LIMITATIONS of -x entry else-
            where in this document.

EXAMPLES
               # Default behavior, extension is Rusers
               h2xs rpcsvc/rusers

               # Same, but extension is RUSERS
               h2xs -n RUSERS rpcsvc/rusers

               # Extension is rpcsvc::rusers. Still finds <rpcsvc/rusers.h>
               h2xs rpcsvc::rusers

               # Extension is ONC::RPC.  Still finds <rpcsvc/rusers.h>
               h2xs -n ONC::RPC rpcsvc/rusers

               # Without constant() or AUTOLOAD
               h2xs -c rpcsvc/rusers




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               # Creates templates for an extension named RPC
               h2xs -cfn RPC

               # Extension is ONC::RPC.
               h2xs -cfn ONC::RPC

               # Makefile.PL will look for library -lrpc in
               # additional directory /opt/net/lib
               h2xs rpcsvc/rusers -L/opt/net/lib -lrpc

               # Extension is DCE::rgynbase
               # prefix "sec_rgy_" is dropped from perl function names
               h2xs -n DCE::rgynbase -p sec_rgy_ dce/rgynbase

               # Extension is DCE::rgynbase
               # prefix "sec_rgy_" is dropped from perl function names
               # subroutines are created for sec_rgy_wildcard_name and sec_rgy_wildcard_sid
               h2xs -n DCE::rgynbase -p sec_rgy_ \
               -s sec_rgy_wildcard_name,sec_rgy_wildcard_sid dce/rgynbase

               # Make XS without defines in perl.h, but with function declarations
               # visible from perl.h. Name of the extension is perl1.
               # When scanning perl.h, define -DEXT=extern -DdEXT= -DINIT(x)=
               # Extra backslashes below because the string is passed to shell.
               # Note that a directory with perl header files would
               #  be added automatically to include path.
               h2xs -xAn perl1 -F "-DEXT=extern -DdEXT= -DINIT\(x\)=" perl.h

               # Same with function declaration in proto.h as visible from perl.h.
               h2xs -xAn perl2 perl.h,proto.h

               # Same but select only functions which match /^av_/
               h2xs -M '^av_' -xAn perl2 perl.h,proto.h

               # Same but treat SV* etc as "opaque" types
               h2xs -o '^[S]V \*$' -M '^av_' -xAn perl2 perl.h,proto.h


ENVIRONMENT
       No environment variables are used.

AUTHOR
       Larry Wall and others

SEE ALSO
       the perl manpage, the perlxstut manpage, the ExtU-
       tils::MakeMaker manpage, and the AutoLoader manpage.

DIAGNOSTICS
       The usual warnings if it cannot read or write the files
       involved.

LIMITATIONS of -x
       h2xs would not distinguish whether an argument to a C



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       function which is of the form, say, `int *', is an input,
       output, or input/output parameter.  In particular, argu-
       ment declarations of the form

           int
           foo(n)
               int *n

       should be better rewritten as

           int
           foo(n)
               int &n

       if `n' is an input parameter.

       Additionally, h2xs has no facilities to intuit that a
       function

          int
          foo(addr,l)
               char *addr
               int   l

       takes a pair of address and length of data at this
       address, so it is better to rewrite this function as

           int
           foo(sv)
                   SV *addr
               PREINIT:
                   STRLEN len;
                   char *s;
               CODE:
                   s = SvPV(sv,len);
                   RETVAL = foo(s, len);
               OUTPUT:
                   RETVAL

       or alternately

           static int
           my_foo(SV *sv)
           {
               STRLEN len;
               char *s = SvPV(sv,len);

               return foo(s, len);
           }

           MODULE = foo        PACKAGE = foo   PREFIX = my_






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           int
           foo(sv)
               SV *sv

       See the perlxs manpage and the perlxstut manpage for addi-
       tional details.

HISTORY
       $TEMPLATE_VERSION
               Original version; created by h2xs $H2XS_VERSION
               with options

                 @ARGS


       EOT

       my $exp_doc = <<EOD;

       EXPORT

       None by default.

       EOD if (@const_names and not $opt_P) {
         $exp_doc .= <<EOD; =head2 Exportable constants

         @{[join "\n  ", @const_names]}

       EOD } if (defined $fdecls and @$fdecls and not $opt_P) {
         $exp_doc .= <<EOD; =head2 Exportable functions

       EOD
         $exp_doc .= <<EOD if $opt_p; When accessing these func-
       tions from Perl, prefix `$opt_p' should be removed.

       EOD
         $exp_doc .= <<EOD;
         @{[join "\n  ", @known_fnames{@fnames}]}

       EOD }

       my $pod = <<"END" unless $opt_P; ## Below is stub documen-
       tation for your module. You better edit it!  # #=head1
       NAME # #$module - Perl extension for blah blah blah #
       #=head1 SYNOPSIS # #  use $module; #  blah blah blah #
       #=head1 DESCRIPTION # #Stub documentation for $module,
       created by h2xs. It looks like the #author of the exten-
       sion was negligent enough to leave the stub #unedited.  #
       #Blah blah blah.  #$exp_doc$revhist #=head1 AUTHOR #
       #$author, $email # #=head1 SEE ALSO # #perl(1).  # #=cut
       END

       $pod =~ s/^\#//gm unless $opt_P; print PM $pod unless
       $opt_P;



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       close PM;

       if( ! $opt_X ){ # print XS, unless it is disabled warn
       "Writing $ext$modpname/$modfname.xs\n";

       print XS <<"END"; #include "EXTERN.h" #include "perl.h"
       #include "XSUB.h"

       END if( @path_h ){
           foreach my $path_h (@path_h_ini) {      my($h) =
       $path_h;      $h =~ s#^/usr/include/##;      if ($^O eq
       'VMS') { $h =~ s#.*vms\]#sys/# or $h =~ s#.*[:>\]]##; }
               print XS qq{#include <$h>\n};
           }
           print XS "\n"; }

       my %pointer_typedefs; my %struct_typedefs;

       sub td_is_pointer {
         my $type = shift;
         my $out = $pointer_typedefs{$type};
         return $out if defined $out;
         my $otype = $type;
         $out = ($type =~ /\*$/);
         # This converts only the guys which do not have trailing
       part in the typedef
         if (not $out
             and $typedef_rex and $type =~ s/($type-
       def_rex)/$typedefs_pre{$1}/go) {
           $type = normalize_type($type);
           print "Is-Pointer: Type mutation via typedefs: $otype
       ==> $type\n"
             if $opt_d;
           $out = td_is_pointer($type);
         }
         return ($pointer_typedefs{$otype} = $out); }

       sub td_is_struct {
         my $type = shift;
         my $out = $struct_typedefs{$type};
         return $out if defined $out;
         my $otype = $type;
         $out = ($type =~ /^(struct|union)\b/) &&
       !td_is_pointer($type);
         # This converts only the guys which do not have trailing
       part in the typedef
         if (not $out
             and $typedef_rex and $type =~ s/($type-
       def_rex)/$typedefs_pre{$1}/go) {
           $type = normalize_type($type);
           print "Is-Struct: Type mutation via typedefs: $otype
       ==> $type\n"
             if $opt_d;
           $out = td_is_struct($type);



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         }
         return ($struct_typedefs{$otype} = $out); }

       # Some macros will bomb if you try to return them from a
       double-returning func.  # Say, ((char *)0), or strlen (if
       somebody #define STRLEN strlen).  # Fortunately, we can
       detect both these cases...  sub protect_convert_to_double
       {
         my $in = shift;
         my $val;
         return '' unless defined ($val = $seen_define{$in});
         return '(IV)' if $known_fnames{$val};
         # OUT_t of ((OUT_t)-1):
         return '' unless $val =~
       /^\s*(\(\s*)?\(\s*([^()]*?)\s*\)/;
         td_is_pointer($2) ? '(IV)' : ''; }

       # For each of the generated functions, length($pref) lead-
       ing # letters are already checked.  Moreover, it is recom-
       mended that # the generated functions uses switch on let-
       ter at offset at least # $off + length($pref).  # # The
       given list has length($pref) chars removed at front, it is
       # guarantied that $off leading chars in the rest are the
       same for all # elts of the list.  # # Returns: how at
       which offset it was decided to make a switch, or -1 if
       none.

       sub write_const;

       sub write_const {
         my ($fh, $pref, $off, $list) =
       (shift,shift,shift,shift);
         my %leading;
         my $offarg = length $pref;

         if (@$list == 0) {            # Can happen on the initial iteration only
           print $fh <<"END";
       static double
       constant(char *name, int len, int arg)
       {
           errno = EINVAL;
           return 0;
       }
       END
           return -1;
         }

         if (@$list == 1) {            # Can happen on the initial iteration only
           my $protect = protect_convert_to_double("$pref$list->[0]");








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           print $fh <<"END";
       static double
       constant(char *name, int len, int arg)
       {
           errno = 0;
           if (strEQ(name + $offarg, "$list->[0]")) {  /* $pref removed */
       #ifdef $pref$list->[0]
               return $protect$pref$list->[0];
       #else
               errno = ENOENT;
               return 0;
       #endif
           }
           errno = EINVAL;
           return 0;
       }
       END
           return -1;
         }

         for my $n (@$list) {
           my $c = substr $n, $off, 1;
           $leading{$c} = [] unless exists $leading{$c};
           push @{$leading{$c}}, substr $n, $off + 1;
         }

         if (keys(%leading) == 1) {
           return 1 + write_const $fh, $pref, $off + 1, $list;
         }

         my $leader = substr $list->[0], 0, $off;
         foreach my $letter (keys %leading) {
           write_const $fh, "$pref$leader$letter", 0, $leading{$letter}
             if @{$leading{$letter}} > 1;
         }

         my $npref = "_$pref";
         $npref = '' if $pref eq '';

         print $fh <<"END";
       static double
       constant$npref(char *name, int len, int arg)
       {
       END

         print $fh <<"END" if $npref eq '';
           errno = 0;
       END









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         print $fh <<"END" if $off;
           if ($offarg + $off >= len ) {
               errno = EINVAL;
               return 0;
           }
       END

         print $fh <<"END";
           switch (name[$offarg + $off]) {
       END

         foreach my $letter (sort keys %leading) {
           my $let = $letter;
           $let = '\0' if $letter eq '';

           print $fh <<EOP;
           case '$let':
       EOP
           if (@{$leading{$letter}} > 1) {
             # It makes sense to call a function
             if ($off) {
               print $fh <<EOP;
               if (!strnEQ(name + $offarg,"$leader", $off))
                   break;
       EOP
             }
             print $fh <<EOP;
               return constant_$pref$leader$letter(name, len, arg);
       EOP
           }
           else {
             # Do it ourselves
             my $protect
               = protect_convert_to_double("$pref$leader$letter$leading{$letter}[0]");

             print $fh <<EOP;
               if (strEQ(name + $offarg, "$leader$letter$leading{$letter}[0]")) {      /* $pref removed */
       #ifdef $pref$leader$letter$leading{$letter}[0]
                   return $protect$pref$leader$letter$leading{$letter}[0];
       #else
                   goto not_there;
       #endif
               }
       EOP
           }
         }
         print $fh <<"END";
           }
           errno = EINVAL;
           return 0;

       not_there:
           errno = ENOENT;
           return 0; }



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       END

       }

       if( ! $opt_c ) {
         print XS <<"END"; static int not_here(char *s) {
           croak("$module::%s not implemented on this architec-
       ture", s);
           return -1; }

       END

         write_const(\*XS, '', 0, \@const_names);
       }

       print_tievar_subs(\*XS, $_, $vdecl_hash{$_}) for @vdecls;

       my $prefix; $prefix = "PREFIX = $opt_p" if defined $opt_p;

       # Now switch from C to XS by issuing the first MODULE dec-
       laration: print XS <<"END";

       MODULE = $module         PACKAGE = $module        $prefix

       END

       foreach (sort keys %const_xsub) {
           print XS <<"END"; char * $_()

           CODE:
       #ifdef $_
               RETVAL = $_;
       #else
               croak("Your vendor has not defined the $module macro $_");
       #endif

           OUTPUT:
               RETVAL

       END }

       # If a constant() function was written then output a cor-
       responding # XS declaration: print XS <<"END" unless
       $opt_c;

       double constant(sv,arg)
           PREINIT:      STRLEN         len;
           INPUT:      SV *      sv      char *         s =
       SvPV(sv, len);      int       arg
           CODE:      RETVAL = constant(s,len,arg);
           OUTPUT:      RETVAL

       END




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       my %seen_decl; my %typemap;

       sub print_decl {
         my $fh = shift;
         my $decl = shift;
         my ($type, $name, $args) = @$decl;
         return if $seen_decl{$name}++; # Need to do the same for
       docs as well?

         my @argnames = map {$_->[1]} @$args;
         my @argtypes = map { normalize_type( $_->[0], 1 ) } @$args;
         if ($opt_k) {
           s/^\s*const\b\s*// for @argtypes;
         }
         my @argarrays = map { $_->[4] || '' } @$args;
         my $numargs = @$args;
         if ($numargs and $argtypes[-1] eq '...') {
           $numargs--;
           $argnames[-1] = '...';
         }
         local $" = ', ';
         $type = normalize_type($type, 1);

         print $fh <<"EOP";

       $type $name(@argnames) EOP

         for my $arg (0 .. $numargs - 1) {
           print $fh <<"EOP";
               $argtypes[$arg] $argnames[$arg]$argarrays[$arg]
       EOP
         }
       }

       sub print_tievar_subs {
         my($fh, $name, $type) = @_;
         print $fh <<END; I32 _get_$name(IV index, SV *sv) {
           dSP;
           PUSHMARK(SP);
           XPUSHs(sv);
           PUTBACK;
           (void)call_pv("$module\::_get_$name", G_DISCARD);
           return (I32)0; }

       I32 _set_$name(IV index, SV *sv) {
           dSP;
           PUSHMARK(SP);
           XPUSHs(sv);
           PUTBACK;
           (void)call_pv("$module\::_set_$name", G_DISCARD);
           return (I32)0; }

       END }




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       sub print_tievar_xsubs {
         my($fh, $name, $type) = @_;
         print $fh <<END; void _tievar_$name(sv)      SV* sv
           PREINIT:      struct ufuncs uf;
           CODE:      uf.uf_val = &_get_$name;      uf.uf_set =
       &_set_$name;      uf.uf_index = (IV)&_get_$name;
            sv_magic(sv, 0, 'U', (char*)&uf, sizeof(uf));

       void _get_$name(THIS)      $type THIS = NO_INIT
           CODE:      THIS = $name;
           OUTPUT:      SETMAGIC: DISABLE      THIS

       void _set_$name(THIS)      $type THIS
           CODE:      $name = THIS;

       END }

       sub print_accessors {
         my($fh, $name, $struct) = @_;
         return unless defined $struct && $name !~ /\s|_ANON/;
         $name = normalize_type($name);
         my $ptrname = normalize_type("$name *");
         print $fh <<"EOF";

       MODULE = $module         PACKAGE = ${name}        $prefix

       $name * _to_ptr(THIS)      $name THIS = NO_INIT
           PROTOTYPE: \$
           CODE:      if (sv_derived_from(ST(0), "$name")) {
                STRLEN len;          char *s =
       SvPV((SV*)SvRV(ST(0)), len);          if (len !=
       sizeof(THIS))           croak("Size \%d of packed data !=
       expected \%d",                len, sizeof(THIS));
       RETVAL = ($name *)s;      }      else          croak("THIS
       is not of type $name");
           OUTPUT:      RETVAL

       $name new(CLASS)      char *CLASS = NO_INIT
           PROTOTYPE: \$
           CODE:      Zero((void*)&RETVAL, sizeof(RETVAL), char);
           OUTPUT:      RETVAL

       MODULE = $module         PACKAGE =
       ${name}Ptr          $prefix

       EOF
         my @items = @$struct;
         while (@items) {
           my $item = shift @items;
           if ($item->[0] =~ /_ANON/) {
             if (defined $item->[2]) {      push @items, map [
              @$_[0, 1], "$item->[2]_$_->[2]",
       "$item->[2].$_->[2]",      ], @{ $structs{$item->[0]} };
             } else {      push @items, @{ $structs{$item->[0]}



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       };
             }
           } else {
             my $type = normalize_type($item->[0]);
             my $ttype = $structs{$type} ? normalize_type("$type
       *") : $type;
             print $fh <<"EOF"; $ttype $item->[2](THIS, __value =
       NO_INIT)      $ptrname THIS      $type __value
           PROTOTYPE: \$;\$
           CODE:      if (items > 1)          THIS->$item->[-1] =
       __value;      RETVAL = @{[          $type eq $ttype ?
       "THIS->$item->[-1]" : "&(THIS->$item->[-1])"      ]};
           OUTPUT:      RETVAL

       EOF
           }
         } }

       # Should be called before any actual call to normal-
       ize_type().  sub get_typemap {
         # We do not want to read ./typemap by obvios reasons.
         my @tm =  qw(../../../typemap ../../typemap ../typemap);
         my $stdtypemap =  "$Config::Config{privlib}/ExtU-
       tils/typemap";
         unshift @tm, $stdtypemap;
         my $proto_re = "[" . quotemeta('\$%&*@;') . "]" ;

         # Start with useful default values
         $typemap{float} = 'T_DOUBLE';




























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         foreach my $typemap (@tm) {
           next unless -e $typemap ;
           # skip directories, binary files etc.
           warn " Scanning $typemap\n";
           warn("Warning: ignoring non-text typemap file '$typemap'\n"), next
             unless -T $typemap ;
           open(TYPEMAP, $typemap)
             or warn ("Warning: could not open typemap file '$typemap': $!\n"), next;
           my $mode = 'Typemap';
           while (<TYPEMAP>) {
             next if /^\s*\#/;
             if (/^INPUT\s*$/)   { $mode = 'Input'; next; }
             elsif (/^OUTPUT\s*$/)  { $mode = 'Output'; next; }
             elsif (/^TYPEMAP\s*$/) { $mode = 'Typemap'; next; }
             elsif ($mode eq 'Typemap') {
               next if /^\s*($|\#)/ ;
               my ($type, $image);
               if ( ($type, $image) =
                    /^\s*(.*?\S)\s+(\S+)\s*($proto_re*)\s*$/o
                    # This may reference undefined functions:
                    and not ($image eq 'T_PACKED' and $typemap eq $stdtypemap)) {
                 $typemap{normalize_type($type)} = $image;
               }
             }
           }
           close(TYPEMAP) or die "Cannot close $typemap: $!";
         }
         %std_types = %types_seen;
         %types_seen = ();
       }

       sub normalize_type {          # Second arg: do not strip
       const's before \*
         my $type = shift;
         my $do_keep_deep_const = shift;
         # If $do_keep_deep_const this is heuristical only
         my $keep_deep_const = ($do_keep_deep_const ?
       '\b(?![^(,)]*\*)' : '');
         my $ignore_mods
           =
       "(?:\\b(?:(?:__const__|const)$keep_deep_const|static|inline|__inline__)\\b\\s*)*";
         if ($do_keep_deep_const) {  # Keep different compiled
       /RExen/o separately!
           $type =~ s/$ignore_mods//go;
         }
         else {
           $type =~ s/$ignore_mods//go;
         }
         $type =~ s/([^\s\w])/ \1 /g;
         $type =~ s/\s+$//;
         $type =~ s/^\s+//;
         $type =~ s/\s+/ /g;
         $type =~ s/\* (?=\*)/*/g;
         $type =~ s/\. \. \./.../g;



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         $type =~ s/ ,/,/g;
         $types_seen{$type}++
           unless $type eq '...' or $type eq 'void' or
       $std_types{$type};
         $type; }

       my $need_opaque;

       sub assign_typemap_entry {
         my $type = shift;
         my $otype = $type;
         my $entry;
         if ($tmask and $type =~ /$tmask/) {
           print "Type $type matches -o mask\n" if $opt_d;
           $entry = (td_is_struct($type) ? "T_OPAQUE_STRUCT" :
       "T_PTROBJ");
         }
         elsif ($typedef_rex and $type =~ s/($typedef_rex)/$type-
       defs_pre{$1}/go) {
           $type = normalize_type $type;
           print "Type mutation via typedefs: $otype ==> $type\n"
       if $opt_d;
           $entry = assign_typemap_entry($type);
         }
         $entry ||= $typemap{$otype}
           || (td_is_struct($type) ? "T_OPAQUE_STRUCT" :
       "T_PTROBJ");
         $typemap{$otype} = $entry;
         $need_opaque = 1 if $entry eq "T_OPAQUE_STRUCT";
         return $entry; }

       for (@vdecls) {
         print_tievar_xsubs(\*XS, $_, $vdecl_hash{$_}); }

       if ($opt_x) {
         for my $decl (@$fdecls_parsed) { print_decl(\*XS, $decl)
       }
         if ($opt_a) {
           while (my($name, $struct) = each %structs) {
             print_accessors(\*XS, $name, $struct);
           }
         } }

       close XS;

       if (%types_seen) {
         my $type;
         warn "Writing $ext$modpname/typemap\n";
         open TM, ">typemap" or die "Cannot open typemap file for
       write: $!";







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         for $type (sort keys %types_seen) {
           my $entry = assign_typemap_entry $type;
           print TM $type, "\t" x (5 - int((length $type)/8)), "\t$entry\n"
         }

         print TM <<'EOP' if $need_opaque; # Older Perls do not have correct entry
       #############################################################################
       INPUT
       T_OPAQUE_STRUCT
               if (sv_derived_from($arg, \"${ntype}\")) {
                   STRLEN len;
                   char  *s = SvPV((SV*)SvRV($arg), len);

                   if (len != sizeof($var))
                       croak(\"Size %d of packed data != expected %d\",
                               len, sizeof($var));
                   $var = *($type *)s;
               }
               else
                   croak(\"$var is not of type ${ntype}\")
       #############################################################################
       OUTPUT
       T_OPAQUE_STRUCT
               sv_setref_pvn($arg, \"${ntype}\", (char *)&$var, sizeof($var));
       EOP

         close TM or die "Cannot close typemap file for write: $!";
       }

       } # if( ! $opt_X )

       warn "Writing $ext$modpname/Makefile.PL\n"; open(PL,
       ">Makefile.PL") || die "Can't create $ext$modpname/Make-
       file.PL: $!\n";

       print PL <<END; use ExtUtils::MakeMaker; # See lib/ExtU-
       tils/MakeMaker.pm for details of how to influence # the
       contents of the Makefile that is written.  WriteMakefile(
           'NAME'          => '$module',
           'VERSION_FROM'  => '$modfname.pm', # finds \$VERSION
           'PREREQ_PM'          => {}, # e.g., Module::Name =>
       1.1 END if (!$opt_X) { # print C stuff, unless XS is dis-
       abled
         $opt_F = '' unless defined $opt_F;
         print PL <<END;
           'LIBS'          => ['$extralibs'], # e.g., '-lm'
           'DEFINE'        => '$opt_F', # e.g., '-DHAVE_SOME-
       THING'
           'INC'      => '', # e.g., '-I/usr/include/other' END }
       print PL ");\n"; close(PL) || die "Can't close $ext$modp-
       name/Makefile.PL: $!\n";

       warn "Writing $ext$modpname/test.pl\n"; open(EX,
       ">test.pl") || die "Can't create $ext$modpname/test.pl:



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       $!\n"; print EX <<'_END_'; # Before `make install' is per-
       formed this script should be runnable with # `make test'.
       After `make install' it should work as `perl test.pl'

       ######################### We start with some black magic
       to print on failure.

       # Change 1..1 below to 1..last_test_to_print .  # (It may
       become useful if the test is moved to ./t subdirectory.)

       BEGIN { $| = 1; print "1..1\n"; } END {print "not ok 1\n"
       unless $loaded;} _END_ print EX <<_END_; use $module;
       _END_ print EX <<'_END_'; $loaded = 1; print "ok 1\n";

       ######################### End of black magic.

       # Insert your test code below (better if it prints "ok 13"
       # (correspondingly "not ok 13") depending on the success
       of chunk 13 # of the test code):

       _END_ close(EX) || die "Can't close $ext$modpname/test.pl:
       $!\n";

       unless ($opt_C) {
         warn "Writing $ext$modpname/Changes\n";
         $" = ' ';
         open(EX, ">Changes") || die "Can't create $ext$modp-
       name/Changes: $!\n";
         @ARGS = map {/[\s\"\'\`\$*?^|&<>\[\]\{\}\(\)]/ ? "'$_'"
       : $_} @ARGS;
         print EX <<EOP; Revision history for Perl extension
       $module.

       $TEMPLATE_VERSION  @{[scalar localtime]} \t- original ver-
       sion; created by h2xs $H2XS_VERSION with options \t\t@ARGS

       EOP
         close(EX) || die "Can't close $ext$modpname/Changes:
       $!\n"; }

       warn "Writing $ext$modpname/MANIFEST\n"; open(MANI,'>MANI-
       FEST') or die "Can't create MANIFEST: $!"; my @files =
       <*>; if (!@files) {
         eval {opendir(D,'.');};
         unless ($@) { @files = readdir(D); closedir(D); } } if
       (!@files) { @files = map {chomp && $_} `ls`; } if ($^O eq
       'VMS') {
         foreach (@files) {
           # Clip trailing '.' for portability -- non-VMS OSs
       don't expect it
           s%\.$%%;
           # Fix up for case-sensitive file systems
           s/$modfname/$modfname/i && next;
           $_ = "\U$_" if $_ eq 'manifest' or $_ eq 'changes';



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           $_ = 'Makefile.PL' if $_ eq 'makefile.pl';
         } } print MANI join("\n",@files), "\n"; close MANI;























































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