modbus_tcp_listen(3) ==================== NAME ---- modbus_tcp_listen - create and listen a TCP Modbus socket SYNOPSIS -------- *int modbus_tcp_listen(modbus_t *'ctx', int 'nb_connection');* DESCRIPTION ----------- The _modbus_tcp_listen()_ function shall create a socket and listen for 'nb_connection' incoming connections. RETURN VALUE ------------ The _modbus_tcp_listen()_ function shall return a new socket if successful. Otherwise it shall return -1 and set errno. EXAMPLE ------- For a detailed example, see source file bandwith-server-many-up.c provided in tests directory. [source,c] ------------------- ... ctx = modbus_new_tcp("127.0.0.1", 502); if (modbus_connect(ctx) == -1) { fprintf(stderr, "Connection failed: %s\n", modbus_strerror(errno)); modbus_free(ctx); return -1; } /* Handle until 10 established connections */ server_socket = modbus_tcp_listen(ctx, 10); /* Clear the reference set of socket */ FD_ZERO(&refset); /* Add the server socket */ FD_SET(server_socket, &refset); if (select(server_socket + 1, &refset, NULL, NULL, NULL) == -1) { } ... close(server_socket); modbus_free(ctx); ------------------- SEE ALSO -------- linkmb:modbus_tcp_accept[3] linkmb:modbus_tcp_pi_accept[3] linkmb:modbus_tcp_pi_listen[3] AUTHORS ------- The libmodbus documentation was written by Stéphane Raimbault