After setting environment, QProcess::start() no effect.

[wysota]

I have ever set the env like : env <<"PATH = /home/azhang/env/tool.env" ,
but the result is same. Why?

Setting PATH before running QProcess has little sense. What are you trying to obtain this way? Because the only thing I can think about is that you'll be running bash to execute a script that runs some other programs which are not in the system path - but then you could have set that path directly in the script itself.

Besides, "/home/azhang/env/tool.env" doesn't look like a directory name, it's more likely a file, so setting it to PATH doesn't make sense.