[Python-Dev] os.path.normcase rationale? (original) (raw)

James Y Knight foom at fuhm.net
Sat Sep 25 01:36:42 CEST 2010

On Sep 24, 2010, at 10:53 AM, Paul Moore wrote:

On 24 September 2010 15:29, Guido van Rossum <guido at python.org> wrote:

I don't think we should try to reimplement what the filesystem does. I think we should just ask the filesystem (how exactly I haven't figured out yet but I expect it will be more OS-specific than filesystem-specific). It will have to be a new API -- normcase() at least is intended to return a case-flattened name on OSes where case-preserving filesystems are the default, and changing it to look at the filesystem would break too much code. For a new use case we need a new API. I dug into this once, and as far as I could tell, it's possible to get the information on Windows, but there's no way on Linux to "ask the filesystem". From my researches, the standard interfaces a filesystem has to implement on Linux don't offer any means of asking this question. Of course, (a) I'm no Linux expert so what do I know, and (b) it may well be possible to come up with a "good enough" solution by ignoring pathologically annoying theoretical cases. I'm happy to provide Windows code if someone needs it. Paul

An OSX code sketch is available here (summary: call FSPathMakeRef to get an FSRef from a path string, then FSRefMakePath to make it back into a path, which will then have the correct case). And note that it only works if the file actually exists.

http://stackoverflow.com/questions/370186/how-do-i-find-the-correct-case-of-a-filename

It would indeed be useful to have that be available in Python.

James

More information about the Python-Dev mailing list