cc [ flag ... ] file ... -lsip [ library ... ] #include <sip.h> int sip_create_OKack(sip_msg_t response, sip_msg_t ack_msg, char *transport, char *sent_by, int sent_by_port, char *via_params);
The sip_create_OKack() function constructs an ACK request in ack_msg for the final 2XX SIP response. The request line is created using the URI in the CONTACT header from the response. The SIP-Version in the request line is "2.0". The VIA header for the ACK request is created using transport, sent_by, sent_by_port (if non-zero), and via_params (if non-null). The following headers are copied to ack_msg from response:
The CSEQ header is created using the method as ACK and the sequence number from the CSEQ header in response.
The sip_create_OKack() function returns 0 on success and the appropriate error value in case of failure.
The value of errno is not changed by these calls in the event of an error.
On failure, the sip_create_OKack() function could return one of the following errors:
The sip_create_OKack() function can return this error if it does not find a CONTACT header or if it is unable to obtain the URI from the CONTACT header for the request line.
See attributes(5) for descriptions of the following attributes: