comparison vamp-client/ProcessQtTransport.h @ 114:95c94a86c902

Fix maddening failure to start server with space in its path

     ProcessQtTransport(std::string processName) :
         m_completenessChecker(0) {
         m_process = new QProcess();
         m_process->setReadChannel(QProcess::StandardOutput);
         m_process->setProcessChannelMode(QProcess::ForwardedErrorChannel);
-        m_process->start(processName.c_str());
+        QString name(QString::fromStdString(processName));
+
+        // The second argument here is vital, otherwise we get a
+        // different start() overload which parses all command args
+        // out of its first argument only and therefore fails when
+        // name has a space in it. This is such a gotcha that Qt5.6
+        // even introduced a QT_NO_PROCESS_COMBINED_ARGUMENT_START
+        // build flag to disable that overload. Unfortunately I only
+        // discovered that after wasting almost a day on it.
+        m_process->start(name, QStringList());
+        
         if (!m_process->waitForStarted()) {
             if (m_process->state() == QProcess::NotRunning) {
                 QProcess::ProcessError err = m_process->error();
                 if (err == QProcess::FailedToStart) {
                     std::cerr << "Unable to start server process "