tcp_connect() — Open connection to remote host


err_t tcp_connect (struct tcp_pcb *pcb , struct ip_addr *ipaddr , u16_t port , err_t (*connected) (void *arg, struct tcp_pcb *tpcb, err_t err) );


Sets up pcb to connect to the remote host indicated by ipaddr on port port and sends the initial SYN segment which opens the connection.

The tcp_connect() function returns immediately; it does not wait for the connection to be properly set up. Instead, it will call the connected() function specified as the fourth argument when the connection is established. If the connection could not be properly established, either because the other host refused the connection or because the other host didn't answer, the connected() function will be called with its err argument set accordingly.

Return value

The tcp_connect() function can return ERR_MEM if no memory is available for enqueueing the SYN segment. If the SYN indeed was enqueued successfully, the tcp_connect() function returns ERR_OK.