Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.python > #75845

Re: Test for an empty directory that could be very large if it is not empty?

Show all headers | View raw

Roy Smith wrote:

> In article <c4gjqvF8cmiU1@mid.individual.net>,
>  Gregory Ewing <greg.ewing@canterbury.ac.nz> wrote:
> 
>> Virgil Stokes wrote:
>> > How can I
>> > determine if the directory is empty WITHOUT the generation of a list of
>> > the file names
>> 
>> Which platform?
>> 
>> On Windows, I have no idea.
>> 
>> On Unix you can't really do this properly without access
>> to opendir() and readdir(), which Python doesn't currently
>> wrap.
>> 
>> Will the empty directories be newly created, or could they
>> be ones that *used* to contain 200000 files that have since
>> been deleted?
>> 
>> If they're new or nearly new, you could probably tell from
>> looking at the size reported by stat() on the directory.
>> The difference between a fresh empty directory and one with
>> 200000 files in it should be fairly obvious.
>> 
>> A viable strategy might be: If the directory is very large,
>> assume it's not empty. If it's smallish, list its contents
>> to find out for sure.
> 
> I wonder if glob.iglob('*') might help here?

No, the glob module uses os.listdir() under the hood. Therefore iglob() is 
lazy for multiple directories only.

Back to comp.lang.python | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

Test for an empty directory that could be very large if it is not empty? Virgil Stokes <vs@it.uu.se> - 2014-08-06 23:46 +0200
  Re: Test for an empty directory that could be very large if it is not   empty? Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2014-08-07 18:14 +1200
    Re: Test for an empty directory that could be very large if it is not   empty? Cameron Simpson <cs@zip.com.au> - 2014-08-07 17:08 +1000
    Re: Test for an empty directory that could be very large if it is not   empty? Roy Smith <roy@panix.com> - 2014-08-07 07:54 -0400
      Re: Test for an empty directory that could be very large if it is not empty? Peter Otten <__peter__@web.de> - 2014-08-07 14:06 +0200
      Re: Test for an empty directory that could be very large if it is not empty? Tim Chase <python.list@tim.thechases.com> - 2014-08-07 07:05 -0500
        Re: Test for an empty directory that could be very large if it is not empty? Roy Smith <roy@panix.com> - 2014-08-07 08:19 -0400
          Re: Test for an empty directory that could be very large if it is not empty? Tim Chase <python.list@tim.thechases.com> - 2014-08-07 12:37 -0500
            Re: Test for an empty directory that could be very large if it is not empty? Roy Smith <roy@panix.com> - 2014-08-07 21:10 -0400
  Re: Test for an empty directory that could be very large if it is not empty? John Gordon <gordon@panix.com> - 2014-08-07 20:15 +0000

csiph-web