modbus_flush - flush non-transmitted data

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

libmodbus v3.1.6                                   12/09/2019                                    MODBUS_FLUSH(3)

       The modbus_flush() function shall discard data received but not read to the socket or file descriptor
       associated to the context ctx.

       modbus_flush - flush non-transmitted data

       The function shall return 0 or the number of flushed bytes if successful. Otherwise it shall return -1
       and set errno.

intmodbus_flush(modbus_t*ctx);