modbus_connect - Man Page

int modbus_connect(modbus_t *ctx);

The modbus_connect() function shall establish a connection to a Modbus server, a network or a bus using the context information of libmodbus context given in argument.

The function shall return 0 if successful. Otherwise it shall return -1 and set errno to one of the values defined by the system calls of the underlying platform.

modbus_t *ctx;

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;
}

modbus_close(3)

The libmodbus documentation was written by Stéphane Raimbault <stephane.raimbault@gmail.com>

libmodbus(7), modbus_close(3), modbus_new_rtu(3).