2.4 Thread safety

Although the GnuTLS library is thread safe by design, some parts of the cryptographic back-end, such as the random generator, are not. Applications can either call gnutls_global_init which will use the default operating system provided locks (i.e. pthreads on GNU/Linux and CriticalSection on Windows), or specify manually the locking system using the function gnutls_global_set_mutex before calling gnutls_global_init. Setting manually mutexes is recommended only to applications that have full control of the underlying libraries. If this is not the case, the use of the operating system defaults is recommended. Examples are shown below.

#include <gnutls.h>

/* Native threads
 */

int main()
{
   gnutls_global_init();
}

#include <gnutls.h>

/* Other thread packages
 */

int main()
{
   gnutls_global_mutex_set (mutex_init, mutex_deinit, 
                            mutex_lock, mutex_unlock);
   gnutls_global_init();
}