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/*
* Copyright © 2008-2014 Stéphane Raimbault <stephane.raimbault@gmail.com>
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <stdio.h>
#ifndef _MSC_VER
#include <unistd.h>
#endif
#include <stdlib.h>
#include <errno.h>
#include <modbus.h>
int main(void)
{
int s = -1;
modbus_t *ctx;
modbus_mapping_t *mb_mapping;
ctx = modbus_new_tcp("127.0.0.1", 1502);
/* modbus_set_debug(ctx, TRUE); */
mb_mapping = modbus_mapping_new(500, 500, 500, 500);
if (mb_mapping == NULL) {
fprintf(stderr, "Failed to allocate the mapping: %s\n",
modbus_strerror(errno));
modbus_free(ctx);
return -1;
}
s = modbus_tcp_listen(ctx, 1);
modbus_tcp_accept(ctx, &s);
for (;;) {
uint8_t query[MODBUS_TCP_MAX_ADU_LENGTH];
int rc;
rc = modbus_receive(ctx, query);
if (rc > 0) {
/* rc is the query size */
modbus_reply(ctx, query, rc, mb_mapping);
} else if (rc == -1) {
/* Connection closed by the client or error */
break;
}
}
printf("Quit the loop: %s\n", modbus_strerror(errno));
if (s != -1) {
close(s);
}
modbus_mapping_free(mb_mapping);
modbus_close(ctx);
modbus_free(ctx);
return 0;
}
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