Qt Reference Documentation

ping.cpp Example File

dbus/pingpong/ping.cpp
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 #include <stdio.h>

 #include <QtCore/QCoreApplication>
 #include <QtDBus/QtDBus>

 #include "ping-common.h"

 int main(int argc, char **argv)
 {
     QCoreApplication app(argc, argv);

     if (!QDBusConnection::sessionBus().isConnected()) {
         fprintf(stderr, "Cannot connect to the D-Bus session bus.\n"
                 "To start it, run:\n"
                 "\teval `dbus-launch --auto-syntax`\n");
         return 1;
     }

     QDBusInterface iface(SERVICE_NAME, "/", "", QDBusConnection::sessionBus());
     if (iface.isValid()) {
         QDBusReply<QString> reply = iface.call("ping", argc > 1 ? argv[1] : "");
         if (reply.isValid()) {
             printf("Reply was: %s\n", qPrintable(reply.value()));
             return 0;
         }

         fprintf(stderr, "Call failed: %s\n", qPrintable(reply.error().message()));
         return 1;
     }

     fprintf(stderr, "%s\n",
             qPrintable(QDBusConnection::sessionBus().lastError().message()));
     return 1;
 }