[Pythonmac-SIG] Stupid OS.WALK tricks?

[Dinu Gherman]

"Schollnick, Benjamin" <Benjamin.Schollnick@usa.xerox.com>:

> Folks,
> 
> 	I'm attempting to optimize a quick program, but os.walk
> 	is sort of interferring...
> 	
> 	I'm searching a directory tree for graphic file.... using
> 	os.walk, and when it finds the file, it copies it to a local
> 	directory...
> 
> 	The "problem" here, is that I can't figure out how to
> 	stop OS.walk (in the visit function) from "continuing" 
> 	through the rest of the directories, and to just move 
> 	on to the next file... (There should only be one match)..
> 
> 	I figure I'm going to have to write a custom walk to
> 	deal with this scenario....  Does anyone have anything
> 	similiar?  Or suggestions on dealing with this?
> 
> 	Doing a "return" or "Break" during the search doesn't seem
> 	to do this....
> 
> 			- Benjamin


Not exactly a Mac issue, but how about this code written by
/F that you can extend as you like with filters, etc (have
not bothered to remove all unneeded imports):

"""
import os, sys, glob, fnmatch, string
from os.path import basename, dirname, join, islink, isdir, isfile

# Convenience class, as suggested by /F.

class GlobDirectoryWalker:
    "A forward iterator that traverses files in a directory tree."

    def __init__(self, directory, pattern="*"):
        self.stack = [directory]
        self.pattern = pattern
        self.files = []
        self.index = 0

    def __getitem__(self, index):
        while 1:
            try:
                file = self.files[self.index]
                self.index = self.index + 1
            except IndexError:
                # pop next directory from stack
                self.directory = self.stack.pop()
                self.files = os.listdir(self.directory)
                self.index = 0
            else:
                # got a filename
                fullname = join(self.directory, file)
                if isdir(fullname) and not islink(fullname):
                    self.stack.append(fullname)
                if fnmatch.fnmatch(file, self.pattern):
                    return fullname

files = GlobDirectoryWalker(f)
for file in files:
    handle(file) # not implemented
"""

I know os.walk can make you bang your head against the wall in
unexpected ways...

Dinu


--
Dinu C. Gherman
................................................................
"They made a desert and called it peace." (Tacitus)