#161 PDF support broken

[SomeRandomHEFan]

Whenever I try to open a PDF file, I get the following error message:

Traceback (most recent call last):
  File "optparse.py", line 1377, in parse_args
  File "optparse.py", line 1417, in _process_args
  File "optparse.py", line 1470, in _process_long_opt
  File "optparse.py", line 1455, in _match_long_opt
  File "optparse.py", line 1660, in _match_abbrev
optparse.BadOptionError: no such option: --multiprocessing-fork

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "mcomixstarter.py", line 23, in <module>
  File "mcomix/__main__.py", line 24, in main
  File "mcomix/run.py", line 158, in run
  File "mcomix/run.py", line 87, in parse_arguments
  File "optparse.py", line 1379, in parse_args
  File "optparse.py", line 1559, in error
  File "optparse.py", line 1548, in exit
AttributeError: 'NoneType' object has no attribute 'write'

This only started happening when I updated to 3.2.0. PDF support was intact in 3.1.1.

[Oddegamra]

Looks like this is a bug related to the new version of Pyinstaller on Windows, in combination with multiprocessing used by the PDF extractor. The internet claims that calling multiprocessing.freeze_support() is supposed to fix this problem, and we are in fact already calling that function. I can confirm that running the "unfrozen" version from source on Windows also does not exhibit the problem.

[Oddegamra]

Maybe I was mistaken - it seems that the relevant code was refactored out in a4092eb4f2927ce5d600444d0b10c308148ca34d and is no no longer called when running mcomixstarter.py, which happens when MComix is frozen for Windows.

[Oddegamra]

Come to think of it, it seems kind of strange that we have freeze_support() in code paths that are never run on Windows and frozen environment. Maybe we should move it to mcomixstarter.py and just be done with it?

[Ark]

Not sure if you are talking about this, but a code snippet like

mp.freeze_support()
mp.set_start_method('spawn')

is already present in __main__.py.

[Oddegamra]

Yes, that's exactly what I was talking about. This code should be somewhere in the code path that is taken when MComix is run on Windows while frozen by Pyinstaller. From what I can see, PyInstaller is set up to run mcomixstarter.py. This file calls mcomix.__main__.main(). Unfortunately, the mentioned code above is in if __name__ == '__main__', while it was in main() previously when the freeze support was supposedly still working.