application cannot get the running AppImage path

Question

In my application, sometimes I need to find out the path of the application executable. I use QApplication::applicationFilePath() and it works fine. But when I distribute my application as AppImage on Linux, this breaks. It returns the path where the running AppImage was mounted, e.g. /tmp/.mount_MyAppxyzabc/MyApp. But I would need to get the path of the AppImage itself, e.g. /home/vlad/MyApp/MyApp.AppImage. Is this possible to obtain from inside the running application?

Answer 1

I quickly found the answer and I will leave it here for others. At least for AppImages deployed by linuxdeployqt (not sure about other AppImages), the path to the appimage is in environment variable $APPIMAGE.

So in my code I use: QString appImagePath = QProcessEnvironment::systemEnvironment().value(QStringLiteral("APPIMAGE"));

The returned string however ends with path separator '/' so I need to remove it.

Answer 2

The code above doesn't work for me. appImagePath is set to an empty QString. Also, the following:

QProcessEnvironment env(QProcessEnvironment::systemEnvironment());
QStringList tt = env.keys();
QFile outFile("./debug.txt");
outFile.open(QIODevice::WriteOnly | QIODevice::Text);
QTextStream out(&outFile);
for (QStringList::iterator it = tt.begin(); it != tt.end(); ++it)
    out << *it << " " << env.value(*it) << endl;
outFile.close();

works for me in my release build, but doesn't in the appImage

This is on Linux.

Thanks.