Re^2: Testing for a directory handle

On *nix machines it shows the "." and ".." entries. I'm not sure how that works on MSWin. I've left it in as a potential edge case.

Well, as usual for Microsoft software: Don't expect consistent behaviour. Most directories have the . and .. entries. For the root directory of any drive, it heavily depends on the drive type. Some root directories have the . and .. entries, others don't. See Re^6: readdir() on a sysopen() handle? for details.

Alexander

--
Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

Comment on Re^2: Testing for a directory handle

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Re^3: Testing for a directory handle by kcott (Archbishop) on Jan 31, 2018 at 02:27 UTC
Thanks for the additional information regarding this. It doesn't affect me personally (either at work or home) at the moment, and probably won't do in the forseeable future; however, for those working with the MSWin filesystem, this could be important. I suppose the real issue is how this might affect `telldir` in the context of the code I posted. I'm not in a position to test this but I'll attempt to paraphrase in nix parlance. Given a truly empty directory (root or otherwise), e.g. `$ ls -al fred ls: cannot access 'fred': No such file or directory $ mkdir fred $` [download] Where a listing showed $ ls -al fred total 0 $ [download] instead of $ ls -al fred total 0 drwxr-xr-x 2 ken staff 68 Jan 31 12:57 . drwxr-xr-x 18 ken staff 612 Jan 31 12:57 .. $ [download] How would the "`eh`" handle be reported? Just to be clear, that's the one I showed as: `eh is a dirhandle # eh = dirhandle to "pm_1208018_test_dir_empty"`* If someone could test that and report their findings, it could provide useful information to anyone wanting to use this technique in the future. — Ken	[reply] [d/l] [select]

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Re^3: Testing for a directory handle
by kcott (Archbishop) on Jan 31, 2018 at 02:27 UTC

Thanks for the additional information regarding this. It doesn't affect me personally (either at work or home) at the moment, and probably won't do in the forseeable future; however, for those working with the MSWin filesystem, this could be important.

I suppose the real issue is how this might affect telldir in the context of the code I posted. I'm not in a position to test this but I'll attempt to paraphrase in *nix parlance. Given a truly empty directory (root or otherwise), e.g.

$ ls -al fred
ls: cannot access 'fred': No such file or directory
$ mkdir fred
$
[download]

Where a listing showed

$ ls -al fred
total 0
$
[download]

instead of

$ ls -al fred
total 0
drwxr-xr-x  2 ken staff  68 Jan 31 12:57 .
drwxr-xr-x 18 ken staff 612 Jan 31 12:57 ..
$
[download]

How would the "eh" handle be reported? Just to be clear, that's the one I showed as:

eh is a dirhandle # eh = dirhandle to "pm_1208018_test_dir_empty"

If someone could test that and report their findings, it could provide useful information to anyone wanting to use this technique in the future.

— Ken

[reply]
[d/l]
[select]