.. _program_listing_file_src_cmd_o3ds_ping.c:

Program Listing for File o3ds_ping.c
====================================

|exhale_lsh| :ref:`Return to documentation for file <file_src_cmd_o3ds_ping.c>` (``src/cmd/o3ds_ping.c``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   // Based mainly on https://github.com/nanomsg/nng/blob/master/demo/async/client.c
   
   #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)
   {
     nng_socket sock;
     int        rv;
     nng_msg *  msg;
     nng_time   start;
     nng_time   end;
   
     if ((rv = nng_req0_open(&sock)) != 0) {
       fatal("nng_req0_open", rv);
     }
   
     if ((rv = nng_dial(sock, url, NULL, 0)) != 0) {
       fatal("nng_dial", rv);
     }
   
     start = nng_clock();
   
     if ((rv = nng_msg_alloc(&msg, 10)) != 0) {
       fatal("nng_msg_alloc", rv);
     }
   
     nng_msg_append(msg, "test", 5);
   
     // Send a 32 bit uint round-trip to make sure the server is listening
     //if ((rv =   (msg, 0)) != 0) {
     //  fatal("nng_msg_append_u32", rv);
     //}
   
     if ((rv = nng_sendmsg(sock, msg, 0)) != 0) {
       fatal("nng_send", rv);
     }
   
     if ((rv = nng_recvmsg(sock, &msg, 0)) != 0) {
       fatal("nng_recvmsg", rv);
     }
   
     end = nng_clock();
     nng_msg_free(msg);
     nng_close(sock);
   
     printf("Ping took %u milliseconds.\n", (uint32_t)(end - start));
     return (0);
   }
   
   int
   main(int argc, char **argv)
   {
     int rc;
     if (argc != 2) {
       fprintf(stderr, "Usage: %s <url>\n", argv[0]);
       fprintf(stderr, "Example: %s tcp://127.0.0.1:5555\n", argv[0]);
       exit(EXIT_FAILURE);
     }
     rc = client(argv[1]);
     exit(rc == 0 ? EXIT_SUCCESS : EXIT_FAILURE);
   }