os.walk without digging into directories below

Question

Don't use os.walk.

Example:

import os

root = "C:\\"
for item in os.listdir(root):
    if os.path.isfile(os.path.join(root, item)):
        print item

Use the walklevel function.

import os

def walklevel(some_dir, level=1):
    some_dir = some_dir.rstrip(os.path.sep)
    assert os.path.isdir(some_dir)
    num_sep = some_dir.count(os.path.sep)
    for root, dirs, files in os.walk(some_dir):
        yield root, dirs, files
        num_sep_this = root.count(os.path.sep)
        if num_sep + level <= num_sep_this:
            del dirs[:]

It works just like os.walk, but you can pass it a level parameter that indicates how deep the recursion will go.

I think the solution is actually very simple.

use

break

to only do first iteration of the for loop, there must be a more elegant way.

for root, dirs, files in os.walk(dir_name):
    for f in files:
        ...
        ...
    break
...

The first time you call os.walk, it returns tulips for the current directory, then on next loop the contents of the next directory.

Take original script and just add a break.

def _dir_list(self, dir_name, whitelist):
    outputList = []
    for root, dirs, files in os.walk(dir_name):
        for f in files:
            if os.path.splitext(f)[1] in whitelist:
                outputList.append(os.path.join(root, f))
            else:
                self._email_to_("ignore")
        break
    return outputList

The suggestion to use listdir is a good one. The direct answer to your question in Python 2 is root, dirs, files = os.walk(dir_name).next().

The equivalent Python 3 syntax is root, dirs, files = next(os.walk(dir_name))

You could use os.listdir() which returns a list of names (for both files and directories) in a given directory. If you need to distinguish between files and directories, call os.stat() on each name.