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[William R. Wing (Bill Wing)]

On Jun 6, 2012, at 9:45 AM, William R. Wing (Bill Wing) wrote:

> On Jun 6, 2012, at 9:29 AM, Alain Ketterlin wrote:
> 
>> loial <jldunn2000 at gmail.com> writes:
>> 
>>> I have a requirement to test the creation time of a file with the
>>> current time and raise a message if the file is  more than 15 minutes
>>> old.
>>> Platform is Unix.
>>> I have looked at using os.path.getctime for the file creation time and
>>> time.time() for the current time, but is this the best approach?
>> 
>> No. getctime() returns the last "change" time. The creation time is not
>> kept anywhere. This may still match your requirement though. And os.path
>> is the right package to look at for such tasks.
>> 
>> -- Alain.
>> -- 
>> http://mail.python.org/mailman/listinfo/python-list
> 
> If you REALLY want the creation time rather than the last time the file was touched, you will probably have to invoke the subprocess module and call ls -U, something like the following:
> 
> creation_time = subprocess.check_output(["ls", "-U", string_filename_variable])
> 
> The -U option isn't universal, but it does exist in most of the UNIces I'm familiar with.
> 
> -Bill

Addendum, with apologies - I was in too much of a hurry.  The -U option has to be used with -l (at least on my system).  Thus, it would be ls -lU.  Alternatively, you could "stat" the file in a subprocess and then parse the return data to extract the creation date.

-Bill