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| <title>Thread safety</title> |
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| <h1>The XML C library for Gnome</h1> |
| <h2>Thread safety</h2> |
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| <p>Starting with 2.4.7, libxml makes provisions to ensure that concurent |
| 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="mailto:daniel@veillard.com">Daniel Veillard</a></p> |
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