tcp_close - closes TCP connection in an orderly manner
int tcp_close(int s, int64_t deadline);
TCP protocol is a bytestream protocol (i.e. data can be sent via bsend() and received via brecv()) for transporting data among machines.
This function closes a TCP socket cleanly. Unlike hclose() it lets the peer know that it is shutting down and waits till the peer acknowledged the shutdown. If this terminal handshake cannot be done it returns error. The socket is closed even in the case of error.
deadline is a point in time when the operation should time out. Use the now() function to get your current point in time. 0 means immediate timeout, i.e., perform the operation if possible or return without blocking if not. -1 means no deadline, i.e., the call will block forever if the operation cannot be performed.
Zero in case of success. On error, it returns -1 and sets errno to one of the values below.
int rc = tcp_close(s, -1);