Directory tree generator.
For each directory in the directory tree rooted at top (including top
itself, but excluding '.' and '..'), yields a 3-tuple
dirpath, dirnames, filenames
dirpath is a string, the path to the directory. dirnames is a list of
the names of the subdirectories in dirpath (including symlinks to
directories, and excluding '.' and '..').
filenames is a list of the names of the non-directory files in dirpath.
Note that the names in the lists are just names, with no path
components. To get a full path (which begins with top) to a file or
directory in dirpath, do os.path.join(dirpath, name).
If optional arg 'topdown' is true or not specified, the triple for a
directory is generated before the triples for any of its subdirectories
(directories are generated top down). If topdown is false, the triple
for a directory is generated after the triples for all of its
subdirectories (directories are generated bottom up).
When topdown is true, the caller can modify the dirnames list in-place
(e.g., via del or slice assignment), and walk will only recurse into the
subdirectories whose names remain in dirnames; this can be used to prune
the search, or to impose a specific order of visiting. Modifying
dirnames when topdown is false has no effect on the behavior of
os.walk(), since the directories in dirnames have already been generated
by the time dirnames itself is generated. No matter the value of
topdown, the list of subdirectories is retrieved before the tuples for
the directory and its subdirectories are generated.
By default errors from the os.scandir() call are ignored. If
optional arg 'onerror' is specified, it should be a function; it
will be called with one argument, an OSError instance. It can
report the error to continue with the walk, or raise the exception
to abort the walk. Note that the filename is available as the
filename attribute of the exception object.
By default, os.walk does not follow symbolic links to subdirectories on
systems that support them. In order to get this functionality, set the
optional argument 'followlinks' to true.
Caution: if you pass a relative pathname for top, don't change the
current working directory between resumptions of walk. walk never
changes the current directory, and assumes that the client doesn't
either.
Example:
import os
from os.path import join, getsize
for root, dirs, files in os.walk('python/Lib/xml'):
print(root, "consumes ")
print(sum(getsize(join(root, name)) for name in files), end=" ")
print("bytes in", len(files), "non-directory files")
if '__pycache__' in dirs:
dirs.remove('__pycache__') # don't visit __pycache__ directories