1MODBUS_SET_SOCKET(3)           libmodbus Manual           MODBUS_SET_SOCKET(3)
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NAME

6       modbus_set_socket - set socket of the context
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SYNOPSIS

9       int modbus_set_socket(modbus_t *ctx, int s);
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DESCRIPTION

12       The modbus_set_socket() function shall set the socket or file
13       descriptor in the libmodbus context. This function is useful for
14       managing multiple client connections to the same server.
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RETURN VALUE

17       The function shall return 0 if successful. Otherwise it shall return -1
18       and set errno.
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EXAMPLE

21           ctx = modbus_new_tcp("127.0.0.1", 1502);
22           server_socket = modbus_tcp_listen(ctx, NB_CONNECTION);
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24           FD_ZERO(&rdset);
25           FD_SET(server_socket, &rdset);
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27           /* .... */
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29           if (FD_ISSET(master_socket, &rdset)) {
30               modbus_set_socket(ctx, master_socket);
31               rc = modbus_receive(ctx, query);
32               if (rc != -1) {
33                   modbus_reply(ctx, query, rc, mb_mapping);
34               }
35           }
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SEE ALSO

38       modbus_get_socket(3)
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AUTHORS

41       The libmodbus documentation was written by Stéphane Raimbault
42       <stephane.raimbault@gmail.com>
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46libmodbus v3.1.6                  02/04/2022              MODBUS_SET_SOCKET(3)