Can't print from Python script thread to Delphi main thread

[Martybartfast 2]

I emailed @pyscripter about an issue I was having with getting a dynamically created TPythonThread to print to a dynamically created TPythonInputOutput. He suggested I should post here.

I've tried some of the suggested ideas, but alas still no luck with print() from a threaded script appearing on the main thread memo.

 

I have now created a minimal project with my code, see attached. Can anyone explain what I'm doing wrong?! The script seems to run (the for loop reacts as expected), but I just can't see the Print output. Much appreciate any help, thank you!

P4D Showtime test.zip

[pyscripter 796]

Output redirection is not supported with emNewInterpreterOwnGIL.

 

See other threads with a discussion of the limitations of that mode in this forum.

[Martybartfast 2]

Ahhh, yes. If I set ThreadExecMode := emNewState; then I see print output. Hummmm... need to think what to do then.

 

[pyscripter 796]

@Martybartfast

Actually there is an easy solution:

 

Replace TPyThread.ExecuteWithPython with

procedure TPyThread.ExecuteWithPython;
// Run the script
begin
  TPythonModule(PyEngine.IOPythonModule).MultInterpretersSupport := mmiPerInterpreterGIL;
  TPythonModule(PyEngine.IOPythonModule).InitializeForNewInterpreter;
  PyEngine.DoRedirectIO;
  PyEngine.ExecString(FScript);   // Run Python script
end;

and printing should work.

Edited yesterday at 04:57 PM by pyscripter

[pyscripter 796]

@Martybartfast Support for output redirection from sub-interpreters has been committed.    So with the latest version you do need the above workaround.

Edited yesterday at 06:32 PM by pyscripter

[Martybartfast 2]

@pyscripterAwesome stuff!!! Works perfectly now. Thank you so much, and thanks for making such a great set of components 

[Martybartfast 2]

BTW for anyone else doing ThreadExecMode := emNewInterpreterOwnGIL; and using a module, do make sure in your module you set this property: 

MultInterpretersSupport := mmiPerInterpreterGIL;

That cause me a bit of head scratching for a while!