The sdp_add_origin() function adds the ORIGIN (o=) SDP field to the session structure that is specified by the value of the session parameter (sdp_session_t) using the name, id, ver, nettype, addrtype, and address parameters.
Return Values: The sdp_add_origin() function returns 0 when the function completes successfully. When mandatory parameters are not present, the function returns EINVAL. When memory allocation fails, the function returns ENOMEM. The value of errno does not change in the event of an error.