I created external thread ex; // pthread_t thread1; void *makecall() ----> external thread function (example); { pjsua_makecall();----> PjSIP API (example) } ///I create and exectued my external thread i pthread_create (&thread1,NULL,&makecall,NULL); pthread_join(thread1,NULL); I like to register the above thread into pjsip stack. I tried pj_thread_desk var; pj_tread_register("mythread",var,&thread1); is it correct? While when my thread calling pjsua_Makecall() function. it show the abort. what is the reason.. please give clear idea about. how to register external threads with pjsip stack.. Regards, Karthikeyan S Karthikeyan Selvaraj Software Engineer Datacom - IMS Extn: 3602 Make everything as simple as possible, but not simpler- Albert ------------------------------------------------------------------- SASKEN BUSINESS DISCLAIMER: This message may contain confidential, proprietary or legally privileged information. In case you are not the original intended Recipient of the message, you must not, directly or indirectly, use, disclose, distribute, print, or copy any part of this message and you are requested to delete it and inform the sender. Any views expressed in this message are those of the individual sender unless otherwise stated. Nothing contained in this message shall be construed as an offer or acceptance of any offer by Sasken Communication Technologies Limited ("Sasken") unless sent with that express intent and with due authority of Sasken. Sasken has taken enough precautions to prevent the spread of viruses. However the company accepts no liability for any damage caused by any virus transmitted by this email. Read Disclaimer at http://www.sasken.com/extras/mail_disclaimer.html