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// Copyright 2018 Staysail Systems, Inc. <info@staysail.tech>
// Copyright 2018 Capitar IT Group BV <info@capitoar.com>
//
// This software is supplied under the terms of the MIT License, a
// copy of which should be located in the distribution where this
// file was obtained (LICENSE.txt). A copy of the license may also be
// found online at https://opensource.org/licenses/MIT.
//
// This program is just a simple client application for our demo server.
// It is in a separate file to keep the server code clearer to understand.
//
// Our demonstration application layer protocol is simple. The client sends
// a number of milliseconds to wait before responding. The server just gives
// back an empty reply after waiting that long.
// For example:
//
// % ./server tcp://127.0.0.1:5555 &
// % ./client tcp://127.0.0.1:5555 323
// Request took 324 milliseconds.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <nng/nng.h>
#include <nng/protocol/reqrep0/req.h>
#include <nng/supplemental/util/platform.h>
void
fatal(const char *func, int rv)
{
fprintf(stderr, "%s: %s\n", func, nng_strerror(rv));
exit(1);
}
/* The client runs just once, and then returns. */
int
client(const char *url, const char *msecstr)
{
nng_socket sock;
int rv;
nng_msg *msg;
nng_time start;
nng_time end;
unsigned msec;
msec = atoi(msecstr);
if ((rv = nng_req0_open(&sock)) != 0) {
fatal("nng_req0_open", rv);
}
if ((rv = nng_dial(sock, url, NULL,
getenv("NONBLOCK") ? NNG_FLAG_NONBLOCK : 0)) != 0) {
fatal("nng_dial", rv);
}
start = nng_clock();
if ((rv = nng_msg_alloc(&msg, 0)) != 0) {
fatal("nng_msg_alloc", rv);
}
if ((rv = nng_msg_append_u32(msg, msec)) != 0) {
fatal("nng_msg_append_u32", rv);
}
if ((rv = nng_sendmsg(sock, msg, 0)) != 0) {
fatal("nng_sendmsg", rv);
}
if ((rv = nng_recvmsg(sock, &msg, 0)) != 0) {
fatal("nng_recvmsg", rv);
}
end = nng_clock();
nng_msg_free(msg);
nng_socket_close(sock);
printf("Request took %u milliseconds.\n", (uint32_t) (end - start));
return (0);
}
int
main(int argc, char **argv)
{
int rc;
if (argc != 3) {
fprintf(stderr, "Usage: %s <url> <secs>\n", argv[0]);
exit(EXIT_FAILURE);
}
rc = client(argv[1], argv[2]);
exit(rc == 0 ? EXIT_SUCCESS : EXIT_FAILURE);
}
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