There are lots of things you can do using this method. You're not limited to what Qt provides and you can break out of such limitations by carefully selecting a third-party program that provides what you need. One such example is making your own antivirus GUI by utilizing the command-line-only antivirus scanners available on the market, such as Avira ScanCL, Panda Antivirus Command Line Scanner, SAV32CLI, and ClamAV. You can build your own GUI using Qt and essentially send commands to the antivirus process to tell it what to do.