Gnome LogoW3C LogoRed Hat Logo

The XML C library for Gnome

Thread safety

Main Menu
API Indexes
Related links

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:

  • configure the library accordingly using the --with-threads options
  • call xmlInitParser() in the "main" thread before using any of the libxml API (except possibly selecting a different memory allocator)

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:

  • concurrent loading
  • file access resolution
  • catalog access
  • catalog building
  • entities lookup/accesses
  • validation
  • global variables per-thread override
  • memory handling

XPath is supposed to be thread safe now, but this wasn't tested seriously.

Daniel Veillard