Use flock() for file locking by expobrain · Pull Request #513 · gitpython-developers/GitPython

Thanks @expobrain for this valuable contribution, and @Alexxz for the initial review.

Having glanced over the code, I'd believe it has a chance to work given that all unit-tests still succeed. However, I am not quite sure whether I would be willing to downright kill windows support, as fcntl doesn't seem to be supported there. It's a breaking change, asking for a major version increment at least. The alternative could be to have a branching code-paths, which again would be difficult to test on windows as there is no CI setup for it.

Being very honest to myself, then admittedly I don't have access to windows and will not make such an attempt. Maybe there is someone working on windows who would be willing to take over maintaining support for that platform.

I also believe that a major version increment would be a doable precondition for a merge.
@gitpython-developers/contributors (and everyone inclined) please be welcome to chime in, I would not want to make this decision alone. Until there is a consensus, I would refrain from merging this one.