XML::LibXML::Devel man page on Hurd

Man page or keyword search:  
man Server   6387 pages
apropos Keyword Search (all sections)
Output format
Hurd logo
[printable version]

XML::LibXML::Devel(3pmUser Contributed Perl DocumentatiXML::LibXML::Devel(3pm)

NAME
       XML::LibXML::Devel - makes functions from LibXML.xs available

SYNOPSIS
	 /**********************************************
	  * C functions you want to access
	  */
	 xmlNode *return_node();
	 void receive_node(xmlNode *);

	 ###############################################
	 # XS Code
	 void *
	   xs_return_node
	   CODE:
	       RETVAL = return_node();
	   OUTPUT:
	       RETVAL

	 void
	   xs_receive_node
	       void *n
	   CODE:
	       receive_node(n);

	 ###############################################
	 # Perl code
	 use XML::LibXML::Devel;

	 sub return_node
	 {
	   my $raw_node = xs_return_node();
	   my $node = XML::LibXML::Devel::node_to_perl($raw_node);
	   XML::LibXML::Devel::refcnt_inc($raw_node);
	   return $node;
	 }

	 sub receive_node
	 {
	   my ($node) = @_;
	   my $raw_node = XML::LibXML::Devel::node_from_perl($node);
	   xs_receive_node($raw_node);
	   XML::LibXML::Devel::refcnt_inc($raw_node);
	 }

DESCRIPTION
       "XML::LibXML::Devel" makes functions from LibXML.xs available that are
       needed to wrap libxml2 nodes in and out of XML::LibXML::Nodes.  This
       gives cleaner dependencies than using LibXML.so directly.

       To XS a library that uses libxml2 nodes the first step is to do this so
       that xmlNodePtr is passed as void *. These raw nodes are then turned
       into libxml nodes by using this "Devel" functions.

       Be aware that this module is currently rather experimental. The
       function names may change if I XS more functions and introduce a
       reasonable naming convention.

       Be also aware that this module is a great tool to cause segfaults and
       introduce memory leaks. It does however provide a partial cure by
       making "xmlMemUsed" available as "mem_used".

FUNCTIONS
   NODE MANAGEMENT
       node_to_perl
	  node_to_perl($raw_node);

	Returns a LibXML::Node object. This has a proxy node with a reference
	counter and an owner attached. The raw node will be deleted as soon as
	the reference counter reaches zero.  If the C library is keeping a
	pointer to the raw node, you need to call refcnt_inc immediately.  You
	also need to replace xmlFreeNode by a call to refcnt_dec.

       node_to_perl
	  node_from_perl($node);

	Returns a raw node. This is a void * pointer and you can do nothing
	but passing it to functions that treat it as an xmlNodePtr. The raw
	node will be freed as soon as its reference counter reaches zero.  If
	the C library is keeping a pointer to the raw node, you need to call
	refcnt_inc immediately.	 You also need to replace xmlFreeNode by a
	call to refcnt_dec.

       refcnt_inc
	  refcnt_inc($raw_node);

	Increments the raw nodes reference counter. The raw node must already
	be known to perl to have a reference counter.

       refcnt_dec
	  refcnt_dec($raw_node);

	Decrements the raw nodes reference counter and returns the value it
	had before. if the counter becomes zero or less, this method will free
	the proxy node holding the reference counter.  If the node is part of
	a subtree, refcnt_dec will fix the reference counts and delete the
	subtree if it is not required any more.

       refcnt
	  refcnt($raw_node);

	Returns the value of the reference counter.

       fix_owner
	  fix_owner($raw_node, $raw_parent);

	This functions fixes the reference counts for an entire subtree.  it
	is very important to fix an entire subtree after node operations where
	the documents or the owner node may get changed. this method is aware
	about nodes that already belong to a certain owner node.

   MEMORY DEBUGGING
       $ENV{DEBUG_MEMORY}
	  BEGIN {$ENV{DEBUG_MEMORY} = 1;};
	  use XML::LibXML;

	This turns on libxml2 memory debugging. It must be set before
	XML::LibXML is loaded.

       mem_used
	  mem_used();

	Returns the number of bytes currently allocated.

   EXPORT
       None by default.

SEE ALSO
       This was created to support the needs of Apache2::ModXml2. So this can
       serve as an example.

AUTHOR
       Joachim Zobel <jz-2011@heute-morgen.de>

COPYRIGHT AND LICENSE
       Copyright (C) 2011 by Joachim Zobel

       This library is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself, either Perl version 5.10.1 or, at
       your option, any later version of Perl 5 you may have available.

perl v5.18.1			  2013-12-17	       XML::LibXML::Devel(3pm)
[top]

List of man pages available for Hurd

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net