int gnutls_global_init( void);
Since GnuTLS 3.3.0 this function is no longer necessary to be explicitly called. To disable the implicit call (in a library constructor) of this function set the environment variable GNUTLS_NO_EXPLICIT_INIT to 1.
This function performs any required precalculations, detects the supported CPU capabilities and initializes the underlying cryptographic backend. In order to free any resources taken by this call you should gnutls_global_deinit() when gnutls usage is no longer needed.
This function increments a global counter, so that gnutls_global_deinit() only releases resources when it has been called as many times as gnutls_global_init(). This is useful when GnuTLS is used by more than one library in an application. This function can be called many times, but will only do something the first time. It is thread safe since GnuTLS 3.3.0.
A subsequent call of this function if the initial has failed will return the same error code.