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| </style><title>Thread safety</title></head><body bgcolor="#8b7765" text="#000000" link="#a06060" vlink="#000000"><table border="0" width="100%" cellpadding="5" cellspacing="0" align="center"><tr><td width="120"><a href="http://swpat.ffii.org/"><img src="epatents.png" alt="Action against software patents" /></a></td><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 href="http://www.redhat.com/"><img src="redhat.gif" alt="Red Hat Logo" /></a><div align="left"><a href="http://xmlsoft.org/"><img src="Libxml2-Logo-180x168.gif" alt="Made with Libxml2 Logo" /></a></div></td><td><table border="0" width="90%" cellpadding="2" cellspacing="0" align="center" bgcolor="#000000"><tr><td><table width="100%" border="0" cellspacing="1" cellpadding="3" bgcolor="#fffacd"><tr><td align="center"><h1>The XML C parser and toolkit of Gnome</h1><h2>Thread 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bgcolor="#000000"><tr><td><table border="0" cellpadding="3" cellspacing="1" width="100%"><tr><td bgcolor="#fffacd"><p>Starting with 2.4.7, libxml2 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 |
| libxml2 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> |