src/api/api_msg.c

712   conn->linger = -1;
877     /* check linger possibilites before calling tcp_close */
879     /* linger enabled/required at all? (i.e. is there untransmitted data left?) */
880     if ((conn->linger >= 0) && (conn->pcb.tcp->unsent || conn->pcb.tcp->unacked)) {
881       if ((conn->linger == 0)) {
882         /* data left but linger prevents waiting */
885       } else if (conn->linger > 0) {
886         /* data left and linger says we should wait */
888           /* data left on a nonblocking netconn -> cannot linger */
891           (conn->linger * 1000)) {
892           /* data left but linger timeout has expired (this happens on further
934       if (conn->linger >= 0) {
935         /* use linger timeout (seconds) */
936         close_timeout = conn->linger * 1000U;