So, seems to be same stuff with pthread_mutex_init() and pthread_mutexattr_init(). ;( Best regards, Konstantin Prokazoff Center Of Excellence, S_V_R Ltd., Kyiv HQs, Ukraine Official business-partner & DevConnect member of Avaya Inc. Regional development & support center of Digium Inc. Tel. +38 044 594 1781, ext. 1038 Fax. +38 044 234 0455