krb5_set_trace_callback -  Specify a callback function for trace events. 
=========================================================================

..

.. c:function:: krb5_error_code krb5_set_trace_callback(krb5_context context, krb5_trace_callback fn, void * cb_data)

..


:param:

	          **[in]** **context** - Library context

	          **[in]** **fn** - Callback function

	          **[in]** **cb_data** - Callback data


..



:return:
         -  Returns KRB5_TRACE_NOSUPP if tracing is not supported in the library (unless fn is NULL). 

..







Specify a callback for trace events occurring in krb5 operations performed within *context* . *fn* will be invoked with *context* as the first argument, *cb_data* as the last argument, and a pointer to a krb5_trace_info as the second argument. If the trace callback is reset via this function or *context* is destroyed, *fn* will be invoked with a NULL second argument so it can clean up *cb_data* . Supply a NULL value for *fn* to disable trace callbacks within *context* .










..






.. note::

	 This function overrides the information passed through the *KRB5_TRACE* environment variable.
 


.. note::

	 First introduced in 1.9
 

