Test/EVSE/GPL/libmodbus-3.1.6/doc/modbus_set_socket.txt

modbus_set_socket(3)
====================


NAME
----
modbus_set_socket - set socket of the context


SYNOPSIS
--------
*int modbus_set_socket(modbus_t *'ctx', int 's');*


DESCRIPTION
-----------
The *modbus_set_socket()* function shall set the socket or file descriptor in
the libmodbus context. This function is useful for managing multiple client
connections to the same server.


RETURN VALUE
------------
The function shall return 0 if successful. Otherwise it shall return -1 and set errno.


EXAMPLE
-------
[source,c]
-------------------
ctx = modbus_new_tcp("127.0.0.1", 1502);
server_socket = modbus_tcp_listen(ctx, NB_CONNECTION);

FD_ZERO(&rdset);
FD_SET(server_socket, &rdset);

/* .... */

if (FD_ISSET(master_socket, &rdset)) {
    modbus_set_socket(ctx, master_socket);
    rc = modbus_receive(ctx, query);
    if (rc != -1) {
        modbus_reply(ctx, query, rc, mb_mapping);
    }
}
-------------------

SEE ALSO
--------
linkmb:modbus_get_socket[3]


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