RFE: find <path> -d -size 0 => doesn't find empty directories

Brian Inglis Brian.Inglis@SystematicSw.ab.ca
Fri Nov 2 05:05:00 GMT 2018

On 2018-11-01 10:12, Andrey Repin wrote:
> L A Walsh wrote:
>> Unfortunately, due to directories really not being in the user
>> disk data space, but in the MFT(zone) (I think), the size
>> comes back as zero ('0') for directories.

>> Would it be possible (if not problematic) for the cygwin
>> emulation layer to return some non-zero value if the
>> directory has actual entries in it (ignoring structural
>> values like "." and "..")?  Maybe return as 'size' either
>> a dummy number proportional to #entries (like 10*#entries),
>> or something like summing up actual number (+1) of characters
>> in the file list?

>> Would that be difficult to do, or add?

> Having something to this extent would be useful in case of searching for
> directories with too many files, for example.

> I'd vote for something like (entries << 7), which is closer to an average ext2
> counter. No need to ignore anything.

I believe readdir(3) overhead is already high, and adding extraneous lookups to
add metadata which is not readily available under NTFS/exFAT would slow it even
Do you really want readdir(3) or stat(3) to recurse to sum the entry sizes for
each subdirectory?
Some of us have some large messy directories more reminiscent of Unix systems
than typical of Windows systems.

$ time du -sh /tmp/
91M     /tmp/

real    0m5.125s
user    0m0.125s
sys     0m1.077s
$ time du -sh /var/log/
496M    /var/log/

real    0m42.725s
user    0m0.687s
sys     0m9.139s

Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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