<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/1999/REC-html401-19991224/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> <link rel="SHORTCUT ICON" href="/favicon.ico"> <style type="text/css"><!-- TD {font-family: Verdana,Arial,Helvetica} BODY {font-family: Verdana,Arial,Helvetica; margin-top: 2em; margin-left: 0em; margin-right: 0em} H1 {font-family: Verdana,Arial,Helvetica} H2 {font-family: Verdana,Arial,Helvetica} H3 {font-family: Verdana,Arial,Helvetica} A:link, A:visited, A:active { text-decoration: underline } --></style> <title>Thread safety</title> </head> <body bgcolor="#8b7765" text="#000000" link="#000000" vlink="#000000"> <table border="0" width="100%" cellpadding="5" cellspacing="0" align="center"><tr> <td width="180"> <a href="http://www.gnome.org/"><img src="gnome2.png" alt="Gnome2 Logo"></a><a href="http://www.w3.org/Status"><img src="w3c.png" alt="W3C Logo"></a><a 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align="center"><center><b>Related links</b></center></td></tr> <tr><td bgcolor="#fffacd"><ul> <li><a href="http://mail.gnome.org/archives/xml/">Mail archive</a></li> <li><a href="http://xmlsoft.org/XSLT/">XSLT libxslt</a></li> <li><a href="http://phd.cs.unibo.it/gdome2/">DOM gdome2</a></li> <li><a href="http://www.aleksey.com/xmlsec/">XML-DSig xmlsec</a></li> <li><a href="ftp://xmlsoft.org/">FTP</a></li> <li><a href="http://www.zlatkovic.com/projects/libxml/">Windows binaries</a></li> <li><a href="http://garypennington.net/libxml2/">Solaris binaries</a></li> <li><a href="http://www.zveno.com/open_source/libxml2xslt.html">MacOsX binaries</a></li> <li><a href="http://sourceforge.net/projects/libxml2-pas/">Pascal bindings</a></li> <li><a href="http://bugzilla.gnome.org/buglist.cgi?product=libxml&product=libxml2">Bug Tracker</a></li> </ul></td></tr> </table> <table width="100%" border="0" cellspacing="1" cellpadding="3"> <tr><td colspan="1" bgcolor="#eecfa1" align="center"><center><b>API Indexes</b></center></td></tr> <tr><td bgcolor="#fffacd"><ul> <li><a href="APIchunk0.html">Alphabetic</a></li> <li><a href="APIconstructors.html">Constructors</a></li> <li><a href="APIfunctions.html">Functions/Types</a></li> <li><a href="APIfiles.html">Modules</a></li> <li><a href="APIsymbols.html">Symbols</a></li> </ul></td></tr> </table> </td></tr></table></td> <td valign="top" bgcolor="#8b7765"><table border="0" cellspacing="0" cellpadding="1" width="100%"><tr><td><table border="0" cellspacing="0" cellpadding="1" width="100%" bgcolor="#000000"><tr><td><table border="0" cellpadding="3" cellspacing="1" width="100%"><tr><td bgcolor="#fffacd"> <p>Starting with 2.4.7, libxml makes provisions to ensure that concurrent threads can safely work in parallel parsing different documents. There is however a couple of things to do to ensure it:</p> <ul> <li>configure the library accordingly using the --with-threads options</li> <li>call xmlInitParser() in the "main" thread before using any of the libxml API (except possibly selecting a different memory allocator)</li> </ul> <p>Note that the thread safety cannot be ensured for multiple threads sharing the same document, the locking must be done at the application level, libxml exports a basic mutex and reentrant mutexes API in <libxml/threads.h>. The parts of the library checked for thread safety are:</p> <ul> <li>concurrent loading</li> <li>file access resolution</li> <li>catalog access</li> <li>catalog building</li> <li>entities lookup/accesses</li> <li>validation</li> <li>global variables per-thread override</li> <li>memory handling</li> </ul> <p>XPath is supposed to be thread safe now, but this wasn't tested seriously.</p> <p><a href="bugs.html">Daniel Veillard</a></p> </td></tr></table></td></tr></table></td></tr></table></td> </tr></table></td></tr></table> </body> </html>