as mentioned before you need to include the libraries to link as well , using the option -l (little L) gcc -L /home/sun/Downloads/pjsip/trunk/pjlib/lib/ myapp.c -I/home/sun/Downloads/pjsip/trunk/pjsip/include/ -lLIBRARYNAMEHERE On Aug 1, 2010, at 10:22 AM, Shamun toha md wrote: > gcc -L /home/sun/Downloads/pjsip/trunk/pjlib/lib/ myapp.c -I/home/sun/Downloads/pjsip/trunk/pjsip/include/ ------ Alejandro Orellana Savant Systems, LLC 770 Main Street Osterville, Ma. 02655 (508) 683-2547 (W) (508) 683-2647 (F) Alejandro.Orellana at savantav.com Statement of Confidentiality The contents of this e-mail message and any attachments are confidential and are intended solely for the addressee. The information may also be legally privileged. This transmission is sent in trust, and the sole purpose of delivery to the intended recipient. If you have received this transmission in error, any use, reproduction or dissemination of this transmission is strictly prohibited. If you are not the intended recipient, please immediately notify the sender by reply e-mail or at 508.683-2500 and delete this message and its attachments, if any. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.pjsip.org/pipermail/pjsip_lists.pjsip.org/attachments/20100801/81e88d5a/attachment-0001.html>