HelenOS sources

tcp_conn_send_fin  423 uspace/app/websrv/websrv.c 	rc = tcp_conn_send_fin(conn);
tcp_conn_send_fin  113 uspace/lib/inet/include/inet/tcp.h extern errno_t tcp_conn_send_fin(tcp_conn_t *);
tcp_conn_send_fin  800 uspace/srv/hid/remcons/remcons.c 	tcp_conn_send_fin(user->conn);
HelenOS homepage, sources at GitHub