In the following code fragment occurring twice in zoo_service_loader.c, GetProcAddress or dlsym will return NULL if a user has mistyped the service name (the WPS Identifier parameter):

#ifdef WIN32
	typedef int (CALLBACK* execute_t)(char***,char***,char***);
	execute_t execute=(execute_t)GetProcAddress(so,fname);
#else
	typedef int (*execute_t)(char***,char***,char***);
	execute_t execute=(execute_t)dlsym(so,fname);
#endif

This will cause a crash when attempting to invoke the function at the address given by execute:

*eres=execute(&m,&request_input_real_format,&request_output_real_format);

There should be a check to avoid this happening (with an error message).