Does portalocker support python 3.5.2 win? about portalocker

[aigoncharov]

+1 for Win 10

[vitidev]

+1 for python 3.6

[aigoncharov]

Though it seemed like a simple AttributeError which could be fixed with simple
getattr(msvcrt, 'LK_RLOCK', msvcrt.LK_RLCK)
it goes deeper for me.
Having applied the fix above I stumbled upon another issue: my python interpreter started failing.
The issue is:
msvcrt.locking(file_.fileno(), mode, -1)
If I put a random number instead of -1 it starts working.

[vitidev]

@keenondrums
msvcrt.locking(fd, mode, nbytes) where nbytes -"the locked region of the file extends from the current file position for nbytes bytes, and may continue beyond the end of the file"
We need to lock whole file.

[aigoncharov]

@vitidev I see. I just pointed that if wee need to lock the whole file -1 is not the answer.

[RazerM]

These lines:

savepos = file_.tell()
if savepos:
    file_.seek(0)
try:
    msvcrt.locking(file_.fileno(), mode, -1)

need to be replaced with something like this:

savepos = file_.tell()
file_.seek(0, os.SEEK_END)
size = file_.tell()
file_.seek(0)
try:
    msvcrt.locking(file_.fileno(), mode, size)

I see no indication from the documentation that -1 is a valid value for the third argument. The msvcrt.locking causes Python to silently exit, which must be a Python bug, though.

[RazerM]

After updating 3.5.2 to 3.5.3 and still getting the crash, I verified that 2.7 and 3.4 don't cause a crash then filed a bug: http://bugs.python.org/issue29392

[TWAC]

The msvcrt module uses _locking which says "It is possible to lock bytes past end of file".

Perhaps one can simply lock as much possible, 2147483647? Any larger value gives OverflowError: Python int too large to convert to C long.

@techtonik added -1, what do you think?

[wolph]

It looks like the bug was fixed so that's good :)
http://bugs.python.org/issue29392

Still... doesn't help much with the bug though. Not sure I can help much here guys (no windows) but I'll help with anything I can offer.

[vitidev]

Second bug "AttributeError: module 'msvcrt' has no attribute 'LK_RLOCK'" not fixed in 1.1.0

[wolph]

Oops, Github automatically closed this. I've reopened.

[vitidev]

If fix in line 14 mode = msvcrt.LK_RLOCK -> mode = msvcrt.LK_RLCK
I did not find LK_RLOCK in any python documentation and I think it's a typo

[wolph]

Fixed on develop, I'm releasing a new version today :)

[wolph]

Delaying on that new release a bit, python 3.x on windows still won't work with exclusive locks correctly for me

[wolph]

The new release works perfect for me on Python 2.x and 3.x on Windows, OS X and Linux