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modbus_tcp_pi_listen

Name

modbus_tcp_pi_listen - create and listen a TCP PI Modbus socket (IPv6)

Synopsis

int modbus_tcp_pi_listen(modbus_t *ctx, int nb_connection);

Description

The modbus_tcp_pi_listen() function shall create a socket and listen to maximum nb_connection incoming connections on the specified nodes. The context ctx must be allocated and initialized with modbus_new_tcp_pi before to set the node to listen, if node is set to NULL or '0.0.0.0', any addresses will be listen.

Return value

The function shall return a new socket if successful. Otherwise it shall return -1 and set errno.

Example

For detailed examples, see source files in tests directory:

  • unit-test-server.c, simple but handle only one connection
...

ctx = modbus_new_tcp_pi("::0", "502");
s = modbus_tcp_pi_listen(ctx, 1);
modbus_tcp_pi_accept(ctx, &s);

for (;;) {
    rc = modbus_receive(ctx, query);
    modbus_replay(ctx, query, rc, mb_mapping);
}
...

modbus_close(s);
modbus_free(ctx);
  • bandwidth-server-many-up.c, handles several connections at once

See also