1
r"""OS routines for Mac, NT, or Posix depending on what system we're on.
4
- all functions from posix, nt, os2, or ce, e.g. unlink, stat, etc.
5
- os.path is one of the modules posixpath, or ntpath
6
- os.name is 'posix', 'nt', 'os2', 'ce' or 'riscos'
7
- os.curdir is a string representing the current directory ('.' or ':')
8
- os.pardir is a string representing the parent directory ('..' or '::')
9
- os.sep is the (or a most common) pathname separator ('/' or ':' or '\\')
10
- os.extsep is the extension separator ('.' or '/')
11
- os.altsep is the alternate pathname separator (None or '/')
12
- os.pathsep is the component separator used in $PATH etc
13
- os.linesep is the line separator in text files ('\r' or '\n' or '\r\n')
14
- os.defpath is the default search path for executables
15
- os.devnull is the file path of the null device ('/dev/null', etc.)
17
Programs that import and use 'os' stand a better chance of being
18
portable between different platforms. Of course, they must then
19
only use functions that are defined by all platforms (e.g., unlink
20
and opendir), and leave all pathname manipulation to os.path
21
(e.g., split and join).
28
_names = sys.builtin_module_names
30
# Note: more names are added to __all__ later.
31
__all__ = ["altsep", "curdir", "pardir", "sep", "extsep", "pathsep", "linesep",
32
"defpath", "name", "path", "devnull",
33
"SEEK_SET", "SEEK_CUR", "SEEK_END"]
35
def _get_exports_list(module):
37
return list(module.__all__)
38
except AttributeError:
39
return [n for n in dir(module) if n[0] != '_']
46
from posix import _exit
49
import posixpath as path
52
__all__.extend(_get_exports_list(posix))
66
__all__.extend(_get_exports_list(nt))
77
if sys.version.find('EMX GCC') == -1:
80
import os2emxpath as path
81
from _emx_link import link
84
__all__.extend(_get_exports_list(os2))
95
# We can use the standard Windows path.
99
__all__.extend(_get_exports_list(ce))
102
elif 'riscos' in _names:
107
from riscos import _exit
110
import riscospath as path
113
__all__.extend(_get_exports_list(riscos))
117
raise ImportError, 'no os specific module found'
119
sys.modules['os.path'] = path
120
from os.path import (curdir, pardir, sep, pathsep, defpath, extsep, altsep,
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# Python uses fixed values for the SEEK_ constants; they are mapped
126
# to native constants if necessary in posixmodule.c
133
# Super directory utilities.
134
# (Inspired by Eric Raymond; the doc strings are mostly his)
136
def makedirs(name, mode=0777):
137
"""makedirs(path [, mode=0777])
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Super-mkdir; create a leaf directory and all intermediate ones.
140
Works like mkdir, except that any intermediate path segment (not
141
just the rightmost) will be created if it does not exist. This is
145
head, tail = path.split(name)
147
head, tail = path.split(head)
148
if head and tail and not path.exists(head):
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# be happy if someone already created the path
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if e.errno != errno.EEXIST:
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if tail == curdir: # xxx/newdir/. exists if xxx/newdir exists
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def removedirs(name):
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Super-rmdir; remove a leaf directory and all empty intermediate
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ones. Works like rmdir except that, if the leaf directory is
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successfully removed, directories corresponding to rightmost path
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segments will be pruned away until either the whole path is
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consumed or an error occurs. Errors during this latter phase are
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ignored -- they generally mean that a directory was not empty.
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head, tail = path.split(name)
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head, tail = path.split(head)
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head, tail = path.split(head)
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def renames(old, new):
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Super-rename; create directories as necessary and delete any left
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empty. Works like rename, except creation of any intermediate
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directories needed to make the new pathname good is attempted
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first. After the rename, directories corresponding to rightmost
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path segments of the old name will be pruned way until either the
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whole path is consumed or a nonempty directory is found.
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Note: this function can fail with the new directory structure made
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if you lack permissions needed to unlink the leaf directory or
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head, tail = path.split(new)
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if head and tail and not path.exists(head):
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head, tail = path.split(old)
207
__all__.extend(["makedirs", "removedirs", "renames"])
209
def walk(top, topdown=True, onerror=None, followlinks=False):
210
"""Directory tree generator.
212
For each directory in the directory tree rooted at top (including top
213
itself, but excluding '.' and '..'), yields a 3-tuple
215
dirpath, dirnames, filenames
217
dirpath is a string, the path to the directory. dirnames is a list of
218
the names of the subdirectories in dirpath (excluding '.' and '..').
219
filenames is a list of the names of the non-directory files in dirpath.
220
Note that the names in the lists are just names, with no path components.
221
To get a full path (which begins with top) to a file or directory in
222
dirpath, do os.path.join(dirpath, name).
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If optional arg 'topdown' is true or not specified, the triple for a
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directory is generated before the triples for any of its subdirectories
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(directories are generated top down). If topdown is false, the triple
227
for a directory is generated after the triples for all of its
228
subdirectories (directories are generated bottom up).
230
When topdown is true, the caller can modify the dirnames list in-place
231
(e.g., via del or slice assignment), and walk will only recurse into the
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subdirectories whose names remain in dirnames; this can be used to prune
233
the search, or to impose a specific order of visiting. Modifying
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dirnames when topdown is false is ineffective, since the directories in
235
dirnames have already been generated by the time dirnames itself is
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By default errors from the os.listdir() call are ignored. If
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optional arg 'onerror' is specified, it should be a function; it
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will be called with one argument, an os.error instance. It can
241
report the error to continue with the walk, or raise the exception
242
to abort the walk. Note that the filename is available as the
243
filename attribute of the exception object.
245
By default, os.walk does not follow symbolic links to subdirectories on
246
systems that support them. In order to get this functionality, set the
247
optional argument 'followlinks' to true.
249
Caution: if you pass a relative pathname for top, don't change the
250
current working directory between resumptions of walk. walk never
251
changes the current directory, and assumes that the client doesn't
257
from os.path import join, getsize
258
for root, dirs, files in os.walk('python/Lib/email'):
259
print root, "consumes",
260
print sum([getsize(join(root, name)) for name in files]),
261
print "bytes in", len(files), "non-directory files"
263
dirs.remove('CVS') # don't visit CVS directories
266
from os.path import join, isdir, islink
268
# We may not have read permission for top, in which case we can't
269
# get a list of the files the directory contains. os.path.walk
270
# always suppressed the exception then, rather than blow up for a
271
# minor reason when (say) a thousand readable directories are still
272
# left to visit. That logic is copied here.
274
# Note that listdir and error are globals in this module due
275
# to earlier import-*.
278
if onerror is not None:
282
dirs, nondirs = [], []
284
if isdir(join(top, name)):
290
yield top, dirs, nondirs
292
path = join(top, name)
293
if followlinks or not islink(path):
294
for x in walk(path, topdown, onerror, followlinks):
297
yield top, dirs, nondirs
299
__all__.append("walk")
301
# Make sure os.environ exists, at least
307
def execl(file, *args):
308
"""execl(file, *args)
310
Execute the executable file with argument list args, replacing the
314
def execle(file, *args):
315
"""execle(file, *args, env)
317
Execute the executable file with argument list args and
318
environment env, replacing the current process. """
320
execve(file, args[:-1], env)
322
def execlp(file, *args):
323
"""execlp(file, *args)
325
Execute the executable file (which is searched for along $PATH)
326
with argument list args, replacing the current process. """
329
def execlpe(file, *args):
330
"""execlpe(file, *args, env)
332
Execute the executable file (which is searched for along $PATH)
333
with argument list args and environment env, replacing the current
336
execvpe(file, args[:-1], env)
338
def execvp(file, args):
341
Execute the executable file (which is searched for along $PATH)
342
with argument list args, replacing the current process.
343
args may be a list or tuple of strings. """
346
def execvpe(file, args, env):
347
"""execvpe(file, args, env)
349
Execute the executable file (which is searched for along $PATH)
350
with argument list args and environment env , replacing the
352
args may be a list or tuple of strings. """
353
_execvpe(file, args, env)
355
__all__.extend(["execl","execle","execlp","execlpe","execvp","execvpe"])
357
def _execvpe(file, args, env=None):
360
argrest = (args, env)
366
head, tail = path.split(file)
371
envpath = env['PATH']
374
PATH = envpath.split(pathsep)
378
fullname = path.join(dir, file)
380
func(fullname, *argrest)
382
tb = sys.exc_info()[2]
383
if (e.errno != errno.ENOENT and e.errno != errno.ENOTDIR
384
and saved_exc is None):
388
raise error, saved_exc, saved_tb
391
# Change environ to automatically call putenv() if it exists
393
# This will fail if there's no putenv
400
# Fake unsetenv() for Windows
401
# not sure about os2 here but
402
# I'm guessing they are the same.
404
if name in ('os2', 'nt'):
409
# On RISC OS, all env access goes through getenv and putenv
410
from riscosenviron import _Environ
411
elif name in ('os2', 'nt'): # Where Env Var Names Must Be UPPERCASE
412
# But we store them as upper case
413
class _Environ(UserDict.IterableUserDict):
414
def __init__(self, environ):
415
UserDict.UserDict.__init__(self)
417
for k, v in environ.items():
419
def __setitem__(self, key, item):
421
self.data[key.upper()] = item
422
def __getitem__(self, key):
423
return self.data[key.upper()]
427
def __delitem__(self, key):
428
del self.data[key.upper()]
430
def __delitem__(self, key):
432
del self.data[key.upper()]
434
for key in self.data.keys():
437
def pop(self, key, *args):
439
return self.data.pop(key.upper(), *args)
440
def has_key(self, key):
441
return key.upper() in self.data
442
def __contains__(self, key):
443
return key.upper() in self.data
444
def get(self, key, failobj=None):
445
return self.data.get(key.upper(), failobj)
446
def update(self, dict=None, **kwargs):
450
except AttributeError:
451
# List of (key, value)
456
# cannot use items(), since mappings
465
else: # Where Env Var Names Can Be Mixed Case
466
class _Environ(UserDict.IterableUserDict):
467
def __init__(self, environ):
468
UserDict.UserDict.__init__(self)
470
def __setitem__(self, key, item):
472
self.data[key] = item
473
def update(self, dict=None, **kwargs):
477
except AttributeError:
478
# List of (key, value)
483
# cannot use items(), since mappings
494
def __delitem__(self, key):
498
for key in self.data.keys():
501
def pop(self, key, *args):
503
return self.data.pop(key, *args)
508
environ = _Environ(environ)
510
def getenv(key, default=None):
511
"""Get an environment variable, return None if it doesn't exist.
512
The optional second argument can specify an alternate default."""
513
return environ.get(key, default)
514
__all__.append("getenv")
523
# Supply spawn*() (probably only for Unix)
524
if _exists("fork") and not _exists("spawnv") and _exists("execv"):
527
P_NOWAIT = P_NOWAITO = 1
529
# XXX Should we support P_DETACH? I suppose it could fork()**2
530
# and close the std I/O streams. Also, P_OVERLAY is the same
533
def _spawnvef(mode, file, args, env, func):
534
# Internal helper; func is the exec*() function to use
542
func(file, args, env)
548
return pid # Caller is responsible for waiting!
550
wpid, sts = waitpid(pid, 0)
553
elif WIFSIGNALED(sts):
554
return -WTERMSIG(sts)
556
return WEXITSTATUS(sts)
558
raise error, "Not stopped, signaled or exited???"
560
def spawnv(mode, file, args):
561
"""spawnv(mode, file, args) -> integer
563
Execute file with arguments from args in a subprocess.
564
If mode == P_NOWAIT return the pid of the process.
565
If mode == P_WAIT return the process's exit code if it exits normally;
566
otherwise return -SIG, where SIG is the signal that killed it. """
567
return _spawnvef(mode, file, args, None, execv)
569
def spawnve(mode, file, args, env):
570
"""spawnve(mode, file, args, env) -> integer
572
Execute file with arguments from args in a subprocess with the
573
specified environment.
574
If mode == P_NOWAIT return the pid of the process.
575
If mode == P_WAIT return the process's exit code if it exits normally;
576
otherwise return -SIG, where SIG is the signal that killed it. """
577
return _spawnvef(mode, file, args, env, execve)
579
# Note: spawnvp[e] is't currently supported on Windows
581
def spawnvp(mode, file, args):
582
"""spawnvp(mode, file, args) -> integer
584
Execute file (which is looked for along $PATH) with arguments from
585
args in a subprocess.
586
If mode == P_NOWAIT return the pid of the process.
587
If mode == P_WAIT return the process's exit code if it exits normally;
588
otherwise return -SIG, where SIG is the signal that killed it. """
589
return _spawnvef(mode, file, args, None, execvp)
591
def spawnvpe(mode, file, args, env):
592
"""spawnvpe(mode, file, args, env) -> integer
594
Execute file (which is looked for along $PATH) with arguments from
595
args in a subprocess with the supplied environment.
596
If mode == P_NOWAIT return the pid of the process.
597
If mode == P_WAIT return the process's exit code if it exits normally;
598
otherwise return -SIG, where SIG is the signal that killed it. """
599
return _spawnvef(mode, file, args, env, execvpe)
601
if _exists("spawnv"):
602
# These aren't supplied by the basic Windows code
603
# but can be easily implemented in Python
605
def spawnl(mode, file, *args):
606
"""spawnl(mode, file, *args) -> integer
608
Execute file with arguments from args in a subprocess.
609
If mode == P_NOWAIT return the pid of the process.
610
If mode == P_WAIT return the process's exit code if it exits normally;
611
otherwise return -SIG, where SIG is the signal that killed it. """
612
return spawnv(mode, file, args)
614
def spawnle(mode, file, *args):
615
"""spawnle(mode, file, *args, env) -> integer
617
Execute file with arguments from args in a subprocess with the
618
supplied environment.
619
If mode == P_NOWAIT return the pid of the process.
620
If mode == P_WAIT return the process's exit code if it exits normally;
621
otherwise return -SIG, where SIG is the signal that killed it. """
623
return spawnve(mode, file, args[:-1], env)
626
__all__.extend(["spawnv", "spawnve", "spawnl", "spawnle",])
629
if _exists("spawnvp"):
630
# At the moment, Windows doesn't implement spawnvp[e],
631
# so it won't have spawnlp[e] either.
632
def spawnlp(mode, file, *args):
633
"""spawnlp(mode, file, *args) -> integer
635
Execute file (which is looked for along $PATH) with arguments from
636
args in a subprocess with the supplied environment.
637
If mode == P_NOWAIT return the pid of the process.
638
If mode == P_WAIT return the process's exit code if it exits normally;
639
otherwise return -SIG, where SIG is the signal that killed it. """
640
return spawnvp(mode, file, args)
642
def spawnlpe(mode, file, *args):
643
"""spawnlpe(mode, file, *args, env) -> integer
645
Execute file (which is looked for along $PATH) with arguments from
646
args in a subprocess with the supplied environment.
647
If mode == P_NOWAIT return the pid of the process.
648
If mode == P_WAIT return the process's exit code if it exits normally;
649
otherwise return -SIG, where SIG is the signal that killed it. """
651
return spawnvpe(mode, file, args[:-1], env)
654
__all__.extend(["spawnvp", "spawnvpe", "spawnlp", "spawnlpe",])
657
# Supply popen2 etc. (for Unix)
659
if not _exists("popen2"):
660
def popen2(cmd, mode="t", bufsize=-1):
661
"""Execute the shell command 'cmd' in a sub-process. On UNIX, 'cmd'
662
may be a sequence, in which case arguments will be passed directly to
663
the program without shell intervention (as with os.spawnv()). If 'cmd'
664
is a string it will be passed to the shell (as with os.system()). If
665
'bufsize' is specified, it sets the buffer size for the I/O pipes. The
666
file objects (child_stdin, child_stdout) are returned."""
668
msg = "os.popen2 is deprecated. Use the subprocess module."
669
warnings.warn(msg, DeprecationWarning, stacklevel=2)
672
PIPE = subprocess.PIPE
673
p = subprocess.Popen(cmd, shell=True, bufsize=bufsize,
674
stdin=PIPE, stdout=PIPE, close_fds=True)
675
return p.stdin, p.stdout
676
__all__.append("popen2")
678
if not _exists("popen3"):
679
def popen3(cmd, mode="t", bufsize=-1):
680
"""Execute the shell command 'cmd' in a sub-process. On UNIX, 'cmd'
681
may be a sequence, in which case arguments will be passed directly to
682
the program without shell intervention (as with os.spawnv()). If 'cmd'
683
is a string it will be passed to the shell (as with os.system()). If
684
'bufsize' is specified, it sets the buffer size for the I/O pipes. The
685
file objects (child_stdin, child_stdout, child_stderr) are returned."""
687
msg = "os.popen3 is deprecated. Use the subprocess module."
688
warnings.warn(msg, DeprecationWarning, stacklevel=2)
691
PIPE = subprocess.PIPE
692
p = subprocess.Popen(cmd, shell=True, bufsize=bufsize,
693
stdin=PIPE, stdout=PIPE, stderr=PIPE,
695
return p.stdin, p.stdout, p.stderr
696
__all__.append("popen3")
698
if not _exists("popen4"):
699
def popen4(cmd, mode="t", bufsize=-1):
700
"""Execute the shell command 'cmd' in a sub-process. On UNIX, 'cmd'
701
may be a sequence, in which case arguments will be passed directly to
702
the program without shell intervention (as with os.spawnv()). If 'cmd'
703
is a string it will be passed to the shell (as with os.system()). If
704
'bufsize' is specified, it sets the buffer size for the I/O pipes. The
705
file objects (child_stdin, child_stdout_stderr) are returned."""
707
msg = "os.popen4 is deprecated. Use the subprocess module."
708
warnings.warn(msg, DeprecationWarning, stacklevel=2)
711
PIPE = subprocess.PIPE
712
p = subprocess.Popen(cmd, shell=True, bufsize=bufsize,
713
stdin=PIPE, stdout=PIPE,
714
stderr=subprocess.STDOUT, close_fds=True)
715
return p.stdin, p.stdout
716
__all__.append("popen4")
718
import copy_reg as _copy_reg
720
def _make_stat_result(tup, dict):
721
return stat_result(tup, dict)
723
def _pickle_stat_result(sr):
724
(type, args) = sr.__reduce__()
725
return (_make_stat_result, args)
728
_copy_reg.pickle(stat_result, _pickle_stat_result, _make_stat_result)
729
except NameError: # stat_result may not exist
732
def _make_statvfs_result(tup, dict):
733
return statvfs_result(tup, dict)
735
def _pickle_statvfs_result(sr):
736
(type, args) = sr.__reduce__()
737
return (_make_statvfs_result, args)
740
_copy_reg.pickle(statvfs_result, _pickle_statvfs_result,
741
_make_statvfs_result)
742
except NameError: # statvfs_result may not exist
745
if not _exists("urandom"):
749
Return a string of n random bytes suitable for cryptographic use.
753
_urandomfd = open("/dev/urandom", O_RDONLY)
754
except (OSError, IOError):
755
raise NotImplementedError("/dev/urandom (or equivalent) not found")
758
while n - len(bs) >= 1:
759
bs += read(_urandomfd, n - len(bs))
added
removed
Lib/os.py
