""" | |
Path operations common to more than one OS | |
Do not use directly. The OS specific modules import the appropriate | |
functions from this module themselves. | |
""" | |
import os | |
import stat | |
__all__ = ['commonprefix', 'exists', 'getatime', 'getctime', 'getmtime', | |
'getsize', 'isdir', 'isfile'] | |
try: | |
_unicode = unicode | |
except NameError: | |
# If Python is built without Unicode support, the unicode type | |
# will not exist. Fake one. | |
class _unicode(object): | |
pass | |
# Does a path exist? | |
# This is false for dangling symbolic links on systems that support them. | |
def exists(path): | |
"""Test whether a path exists. Returns False for broken symbolic links""" | |
try: | |
os.stat(path) | |
except os.error: | |
return False | |
return True | |
# This follows symbolic links, so both islink() and isdir() can be true | |
# for the same path on systems that support symlinks | |
def isfile(path): | |
"""Test whether a path is a regular file""" | |
try: | |
st = os.stat(path) | |
except os.error: | |
return False | |
return stat.S_ISREG(st.st_mode) | |
# Is a path a directory? | |
# This follows symbolic links, so both islink() and isdir() | |
# can be true for the same path on systems that support symlinks | |
def isdir(s): | |
"""Return true if the pathname refers to an existing directory.""" | |
try: | |
st = os.stat(s) | |
except os.error: | |
return False | |
return stat.S_ISDIR(st.st_mode) | |
def getsize(filename): | |
"""Return the size of a file, reported by os.stat().""" | |
return os.stat(filename).st_size | |
def getmtime(filename): | |
"""Return the last modification time of a file, reported by os.stat().""" | |
return os.stat(filename).st_mtime | |
def getatime(filename): | |
"""Return the last access time of a file, reported by os.stat().""" | |
return os.stat(filename).st_atime | |
def getctime(filename): | |
"""Return the metadata change time of a file, reported by os.stat().""" | |
return os.stat(filename).st_ctime | |
# Return the longest prefix of all list elements. | |
def commonprefix(m): | |
"Given a list of pathnames, returns the longest common leading component" | |
if not m: return '' | |
s1 = min(m) | |
s2 = max(m) | |
for i, c in enumerate(s1): | |
if c != s2[i]: | |
return s1[:i] | |
return s1 | |
# Split a path in root and extension. | |
# The extension is everything starting at the last dot in the last | |
# pathname component; the root is everything before that. | |
# It is always true that root + ext == p. | |
# Generic implementation of splitext, to be parametrized with | |
# the separators | |
def _splitext(p, sep, altsep, extsep): | |
"""Split the extension from a pathname. | |
Extension is everything from the last dot to the end, ignoring | |
leading dots. Returns "(root, ext)"; ext may be empty.""" | |
sepIndex = p.rfind(sep) | |
if altsep: | |
altsepIndex = p.rfind(altsep) | |
sepIndex = max(sepIndex, altsepIndex) | |
dotIndex = p.rfind(extsep) | |
if dotIndex > sepIndex: | |
# skip all leading dots | |
filenameIndex = sepIndex + 1 | |
while filenameIndex < dotIndex: | |
if p[filenameIndex] != extsep: | |
return p[:dotIndex], p[dotIndex:] | |
filenameIndex += 1 | |
return p, '' |