kj wrote:
> In <mailman.1196.1255347115.2807.python-l...@python.org> Dave Angel
> <da...@ieee.org> writes:
>
>>kj wrote:
>>> Perl's directory tree traversal facility is provided by the function
>>> find of the File::Find module. This function accepts an optional
>>> callback, called postprocess, that gets invoked "just before leaving
>>> the currently processed directory." The documentation goes on to
>>> say "This hook is handy for summarizing a directory, such as
>>> calculating its disk usage", which is exactly what I use it for in
>>> a maintenance script.
>>>
>>> This maintenance script is getting long in the tooth, and I've been
>>> meaning to add a few enhancements to it for a while, so I thought
>>> that in the process I'd port it to Python, using the os.walk
>>> function, but I see that os.walk does not have anything like this
>>> File::Find::find's postprocess hook. Is there a good way to simulate
>>> it (without having to roll my own File::Find::find in Python)?
>>>
>>> TIA!
>>>
>>> kynn
>>>
>>>
>>Why would you need a special hook when the os.walk() generator yields
>>exactly once per directory? So whatever work you do on the list of
>>files you get, you can then put the summary logic immediately after.
>
>>Or if you really feel you need a special hook, then write a wrapper for
>>os.walk(), which takes a hook function as a parameter, and after
>>yielding each file in a directory, calls the hook. Looks like about 5
>>lines.
>
> I think you're missing the point. The hook in question has to be
> called *immediately after* all the subtrees that are rooted in
> subdirectories contained in the current directory have been visited
> by os.walk.
>
> I'd love to see your "5 lines" for *that*.
import os
def find(root, process):
for pdf in os.walk(root, topdown=False):
process(*pdf)
def process(path, dirs, files):
print path
find(".", process)
Peter
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