QProcess::execute Environment Variables Expanded Strings - c++

Question

How do I get this to work:
QProcess::execute("%windir%\system32\SnippingTool.exe")
I assume expanded environment variables strings are being ignored by QProcess.
I guess I'll need to parse the string and see if % exists and then get the environment variable to complete the full string path. Sounds like hassle and something that should be handled by QProcess. Am I missing something?
Thanks in advance! :)

Answer 1

If you want to use %windir% directly, you can do something like this:
QProcess::execute("cmd.exe /c start /WAIT "" %windir%\\system32\\SnippingTool.exe");
Else, you can use for example qgetenv("windir") or qEnvironmentVariable("windir") to get the windows folder path.
Hope it helps you.

Answer 2

Thanks to #TomKim answer for handling expanded strings in his answer, I got that problem solved. But unfortunately white spaces caused other issues for me that made me come up with this solution that hopefully will help others. Not the prettiest solution though, but it does exactly I needed for multiple platforms:
void QuickCut::executeProcess(const std::string & szProc, const std::string & szArgs)
{
// QProc won't expand environment variable strings.
// Invoking using the user console will allow for expanded string to work as expected.
#ifdef Q_OS_WIN
QString szCommand = "cmd /c start \"\" \"" + QString::fromStdString(szProc) + "\"";
QString szExt = ".cmd";
#elif Q_OS_UNIX
QString szCommand = "sh -c '" + QString::fromStdString(szProc) + "'";
QString szExt = ".sh";
#endif
QStringList qArgsTmp = QString::fromStdString(szArgs).trimmed().split(",");
for (auto && arg : qArgsTmp)
{
QString argTrimmed = arg.trimmed();
if (argTrimmed.isEmpty()) continue;
szCommand += " " + argTrimmed;
}
qDebug() << "[QuickCut::executeProcess] - Execute Command: " << szCommand;
QString szFilePath = applicationDirPath() + "/tempCmd" + szExt;
QFile file(szFilePath);
file.open(QIODevice::ReadWrite);
QTextStream ts(&file);
ts << szCommand;
file.close();
QProcess::execute(szFilePath);
file.remove();
}