1 r
"""OS routines for Mac, NT, or Posix depending on what system we're on.
4 - all functions from posix, nt, os2, mac, or ce, e.g. unlink, stat, etc.
5 - os.path is one of the modules posixpath, ntpath, or macpath
6 - os.name is 'posix', 'nt', 'os2', 'mac', '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", "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 import macpath
as path
98 __all__
.extend(_get_exports_list(mac
))
109 # We can use the standard Windows path.
110 import ntpath
as path
113 __all__
.extend(_get_exports_list(ce
))
116 elif 'riscos' in _names
:
121 from riscos
import _exit
124 import riscospath
as path
127 __all__
.extend(_get_exports_list(riscos
))
131 raise ImportError, 'no os specific module found'
133 sys
.modules
['os.path'] = path
134 from os
.path
import (curdir
, pardir
, sep
, pathsep
, defpath
, extsep
, altsep
,
139 # Python uses fixed values for the SEEK_ constants; they are mapped
140 # to native constants if necessary in posixmodule.c
147 # Super directory utilities.
148 # (Inspired by Eric Raymond; the doc strings are mostly his)
150 def makedirs(name
, mode
=0777):
151 """makedirs(path [, mode=0777])
153 Super-mkdir; create a leaf directory and all intermediate ones.
154 Works like mkdir, except that any intermediate path segment (not
155 just the rightmost) will be created if it does not exist. This is
159 from errno
import EEXIST
160 head
, tail
= path
.split(name
)
162 head
, tail
= path
.split(head
)
163 if head
and tail
and not path
.exists(head
):
167 # be happy if someone already created the path
168 if e
.errno
!= EEXIST
:
170 if tail
== curdir
: # xxx/newdir/. exists if xxx/newdir exists
174 def removedirs(name
):
177 Super-rmdir; remove a leaf directory and all empty intermediate
178 ones. Works like rmdir except that, if the leaf directory is
179 successfully removed, directories corresponding to rightmost path
180 segments will be pruned away until either the whole path is
181 consumed or an error occurs. Errors during this latter phase are
182 ignored -- they generally mean that a directory was not empty.
186 head
, tail
= path
.split(name
)
188 head
, tail
= path
.split(head
)
194 head
, tail
= path
.split(head
)
196 def renames(old
, new
):
199 Super-rename; create directories as necessary and delete any left
200 empty. Works like rename, except creation of any intermediate
201 directories needed to make the new pathname good is attempted
202 first. After the rename, directories corresponding to rightmost
203 path segments of the old name will be pruned way until either the
204 whole path is consumed or a nonempty directory is found.
206 Note: this function can fail with the new directory structure made
207 if you lack permissions needed to unlink the leaf directory or
211 head
, tail
= path
.split(new
)
212 if head
and tail
and not path
.exists(head
):
215 head
, tail
= path
.split(old
)
222 __all__
.extend(["makedirs", "removedirs", "renames"])
224 def walk(top
, topdown
=True, onerror
=None, followlinks
=False):
225 """Directory tree generator.
227 For each directory in the directory tree rooted at top (including top
228 itself, but excluding '.' and '..'), yields a 3-tuple
230 dirpath, dirnames, filenames
232 dirpath is a string, the path to the directory. dirnames is a list of
233 the names of the subdirectories in dirpath (excluding '.' and '..').
234 filenames is a list of the names of the non-directory files in dirpath.
235 Note that the names in the lists are just names, with no path components.
236 To get a full path (which begins with top) to a file or directory in
237 dirpath, do os.path.join(dirpath, name).
239 If optional arg 'topdown' is true or not specified, the triple for a
240 directory is generated before the triples for any of its subdirectories
241 (directories are generated top down). If topdown is false, the triple
242 for a directory is generated after the triples for all of its
243 subdirectories (directories are generated bottom up).
245 When topdown is true, the caller can modify the dirnames list in-place
246 (e.g., via del or slice assignment), and walk will only recurse into the
247 subdirectories whose names remain in dirnames; this can be used to prune
248 the search, or to impose a specific order of visiting. Modifying
249 dirnames when topdown is false is ineffective, since the directories in
250 dirnames have already been generated by the time dirnames itself is
253 By default errors from the os.listdir() call are ignored. If
254 optional arg 'onerror' is specified, it should be a function; it
255 will be called with one argument, an os.error instance. It can
256 report the error to continue with the walk, or raise the exception
257 to abort the walk. Note that the filename is available as the
258 filename attribute of the exception object.
260 By default, os.walk does not follow symbolic links to subdirectories on
261 systems that support them. In order to get this functionality, set the
262 optional argument 'followlinks' to true.
264 Caution: if you pass a relative pathname for top, don't change the
265 current working directory between resumptions of walk. walk never
266 changes the current directory, and assumes that the client doesn't
271 from os.path import join, getsize
272 for root, dirs, files in walk('python/Lib/email'):
273 print root, "consumes",
274 print sum([getsize(join(root, name)) for name in files]),
275 print "bytes in", len(files), "non-directory files"
277 dirs.remove('CVS') # don't visit CVS directories
280 from os
.path
import join
, isdir
, islink
282 # We may not have read permission for top, in which case we can't
283 # get a list of the files the directory contains. os.path.walk
284 # always suppressed the exception then, rather than blow up for a
285 # minor reason when (say) a thousand readable directories are still
286 # left to visit. That logic is copied here.
288 # Note that listdir and error are globals in this module due
289 # to earlier import-*.
292 if onerror
is not None:
296 dirs
, nondirs
= [], []
298 if isdir(join(top
, name
)):
304 yield top
, dirs
, nondirs
306 path
= join(top
, name
)
307 if followlinks
or not islink(path
):
308 for x
in walk(path
, topdown
, onerror
, followlinks
):
311 yield top
, dirs
, nondirs
313 __all__
.append("walk")
315 # Make sure os.environ exists, at least
321 def execl(file, *args
):
322 """execl(file, *args)
324 Execute the executable file with argument list args, replacing the
328 def execle(file, *args
):
329 """execle(file, *args, env)
331 Execute the executable file with argument list args and
332 environment env, replacing the current process. """
334 execve(file, args
[:-1], env
)
336 def execlp(file, *args
):
337 """execlp(file, *args)
339 Execute the executable file (which is searched for along $PATH)
340 with argument list args, replacing the current process. """
343 def execlpe(file, *args
):
344 """execlpe(file, *args, env)
346 Execute the executable file (which is searched for along $PATH)
347 with argument list args and environment env, replacing the current
350 execvpe(file, args
[:-1], env
)
352 def execvp(file, args
):
355 Execute the executable file (which is searched for along $PATH)
356 with argument list args, replacing the current process.
357 args may be a list or tuple of strings. """
360 def execvpe(file, args
, env
):
361 """execvpe(file, args, env)
363 Execute the executable file (which is searched for along $PATH)
364 with argument list args and environment env , replacing the
366 args may be a list or tuple of strings. """
367 _execvpe(file, args
, env
)
369 __all__
.extend(["execl","execle","execlp","execlpe","execvp","execvpe"])
371 def _execvpe(file, args
, env
=None):
372 from errno
import ENOENT
, ENOTDIR
376 argrest
= (args
, env
)
382 head
, tail
= path
.split(file)
387 envpath
= env
['PATH']
390 PATH
= envpath
.split(pathsep
)
394 fullname
= path
.join(dir, file)
396 func(fullname
, *argrest
)
398 tb
= sys
.exc_info()[2]
399 if (e
.errno
!= ENOENT
and e
.errno
!= ENOTDIR
400 and saved_exc
is None):
404 raise error
, saved_exc
, saved_tb
407 # Change environ to automatically call putenv() if it exists
409 # This will fail if there's no putenv
416 # Fake unsetenv() for Windows
417 # not sure about os2 here but
418 # I'm guessing they are the same.
420 if name
in ('os2', 'nt'):
425 # On RISC OS, all env access goes through getenv and putenv
426 from riscosenviron
import _Environ
427 elif name
in ('os2', 'nt'): # Where Env Var Names Must Be UPPERCASE
428 # But we store them as upper case
429 class _Environ(UserDict
.IterableUserDict
):
430 def __init__(self
, environ
):
431 UserDict
.UserDict
.__init
__(self
)
433 for k
, v
in environ
.items():
435 def __setitem__(self
, key
, item
):
437 self
.data
[key
.upper()] = item
438 def __getitem__(self
, key
):
439 return self
.data
[key
.upper()]
443 def __delitem__(self
, key
):
444 del self
.data
[key
.upper()]
446 def __delitem__(self
, key
):
448 del self
.data
[key
.upper()]
449 def has_key(self
, key
):
450 return key
.upper() in self
.data
451 def __contains__(self
, key
):
452 return key
.upper() in self
.data
453 def get(self
, key
, failobj
=None):
454 return self
.data
.get(key
.upper(), failobj
)
455 def update(self
, dict=None, **kwargs
):
459 except AttributeError:
460 # List of (key, value)
465 # cannot use items(), since mappings
474 else: # Where Env Var Names Can Be Mixed Case
475 class _Environ(UserDict
.IterableUserDict
):
476 def __init__(self
, environ
):
477 UserDict
.UserDict
.__init
__(self
)
479 def __setitem__(self
, key
, item
):
481 self
.data
[key
] = item
482 def update(self
, dict=None, **kwargs
):
486 except AttributeError:
487 # List of (key, value)
492 # cannot use items(), since mappings
503 def __delitem__(self
, key
):
510 environ
= _Environ(environ
)
512 def getenv(key
, default
=None):
513 """Get an environment variable, return None if it doesn't exist.
514 The optional second argument can specify an alternate default."""
515 return environ
.get(key
, default
)
516 __all__
.append("getenv")
525 # Supply spawn*() (probably only for Unix)
526 if _exists("fork") and not _exists("spawnv") and _exists("execv"):
529 P_NOWAIT
= P_NOWAITO
= 1
531 # XXX Should we support P_DETACH? I suppose it could fork()**2
532 # and close the std I/O streams. Also, P_OVERLAY is the same
535 def _spawnvef(mode
, file, args
, env
, func
):
536 # Internal helper; func is the exec*() function to use
544 func(file, args
, env
)
550 return pid
# Caller is responsible for waiting!
552 wpid
, sts
= waitpid(pid
, 0)
555 elif WIFSIGNALED(sts
):
556 return -WTERMSIG(sts
)
558 return WEXITSTATUS(sts
)
560 raise error
, "Not stopped, signaled or exited???"
562 def spawnv(mode
, file, args
):
563 """spawnv(mode, file, args) -> integer
565 Execute file with arguments from args in a subprocess.
566 If mode == P_NOWAIT return the pid of the process.
567 If mode == P_WAIT return the process's exit code if it exits normally;
568 otherwise return -SIG, where SIG is the signal that killed it. """
569 return _spawnvef(mode
, file, args
, None, execv
)
571 def spawnve(mode
, file, args
, env
):
572 """spawnve(mode, file, args, env) -> integer
574 Execute file with arguments from args in a subprocess with the
575 specified environment.
576 If mode == P_NOWAIT return the pid of the process.
577 If mode == P_WAIT return the process's exit code if it exits normally;
578 otherwise return -SIG, where SIG is the signal that killed it. """
579 return _spawnvef(mode
, file, args
, env
, execve
)
581 # Note: spawnvp[e] is't currently supported on Windows
583 def spawnvp(mode
, file, args
):
584 """spawnvp(mode, file, args) -> integer
586 Execute file (which is looked for along $PATH) with arguments from
587 args in a subprocess.
588 If mode == P_NOWAIT return the pid of the process.
589 If mode == P_WAIT return the process's exit code if it exits normally;
590 otherwise return -SIG, where SIG is the signal that killed it. """
591 return _spawnvef(mode
, file, args
, None, execvp
)
593 def spawnvpe(mode
, file, args
, env
):
594 """spawnvpe(mode, file, args, env) -> integer
596 Execute file (which is looked for along $PATH) with arguments from
597 args in a subprocess with the supplied environment.
598 If mode == P_NOWAIT return the pid of the process.
599 If mode == P_WAIT return the process's exit code if it exits normally;
600 otherwise return -SIG, where SIG is the signal that killed it. """
601 return _spawnvef(mode
, file, args
, env
, execvpe
)
603 if _exists("spawnv"):
604 # These aren't supplied by the basic Windows code
605 # but can be easily implemented in Python
607 def spawnl(mode
, file, *args
):
608 """spawnl(mode, file, *args) -> integer
610 Execute file with arguments from args in a subprocess.
611 If mode == P_NOWAIT return the pid of the process.
612 If mode == P_WAIT return the process's exit code if it exits normally;
613 otherwise return -SIG, where SIG is the signal that killed it. """
614 return spawnv(mode
, file, args
)
616 def spawnle(mode
, file, *args
):
617 """spawnle(mode, file, *args, env) -> integer
619 Execute file with arguments from args in a subprocess with the
620 supplied environment.
621 If mode == P_NOWAIT return the pid of the process.
622 If mode == P_WAIT return the process's exit code if it exits normally;
623 otherwise return -SIG, where SIG is the signal that killed it. """
625 return spawnve(mode
, file, args
[:-1], env
)
628 __all__
.extend(["spawnv", "spawnve", "spawnl", "spawnle",])
631 if _exists("spawnvp"):
632 # At the moment, Windows doesn't implement spawnvp[e],
633 # so it won't have spawnlp[e] either.
634 def spawnlp(mode
, file, *args
):
635 """spawnlp(mode, file, *args) -> integer
637 Execute file (which is looked for along $PATH) with arguments from
638 args in a subprocess with the supplied environment.
639 If mode == P_NOWAIT return the pid of the process.
640 If mode == P_WAIT return the process's exit code if it exits normally;
641 otherwise return -SIG, where SIG is the signal that killed it. """
642 return spawnvp(mode
, file, args
)
644 def spawnlpe(mode
, file, *args
):
645 """spawnlpe(mode, file, *args, env) -> integer
647 Execute file (which is looked for along $PATH) with arguments from
648 args in a subprocess with the supplied environment.
649 If mode == P_NOWAIT return the pid of the process.
650 If mode == P_WAIT return the process's exit code if it exits normally;
651 otherwise return -SIG, where SIG is the signal that killed it. """
653 return spawnvpe(mode
, file, args
[:-1], env
)
656 __all__
.extend(["spawnvp", "spawnvpe", "spawnlp", "spawnlpe",])
659 # Supply popen2 etc. (for Unix)
661 if not _exists("popen2"):
662 def popen2(cmd
, mode
="t", bufsize
=-1):
663 """Execute the shell command 'cmd' in a sub-process. On UNIX, 'cmd'
664 may be a sequence, in which case arguments will be passed directly to
665 the program without shell intervention (as with os.spawnv()). If 'cmd'
666 is a string it will be passed to the shell (as with os.system()). If
667 'bufsize' is specified, it sets the buffer size for the I/O pipes. The
668 file objects (child_stdin, child_stdout) are returned."""
670 msg
= "os.popen2 is deprecated. Use the subprocess module."
671 warnings
.warn(msg
, DeprecationWarning, stacklevel
=2)
674 PIPE
= subprocess
.PIPE
675 p
= subprocess
.Popen(cmd
, shell
=True, bufsize
=bufsize
,
676 stdin
=PIPE
, stdout
=PIPE
, close_fds
=True)
677 return p
.stdin
, p
.stdout
678 __all__
.append("popen2")
680 if not _exists("popen3"):
681 def popen3(cmd
, mode
="t", bufsize
=-1):
682 """Execute the shell command 'cmd' in a sub-process. On UNIX, 'cmd'
683 may be a sequence, in which case arguments will be passed directly to
684 the program without shell intervention (as with os.spawnv()). If 'cmd'
685 is a string it will be passed to the shell (as with os.system()). If
686 'bufsize' is specified, it sets the buffer size for the I/O pipes. The
687 file objects (child_stdin, child_stdout, child_stderr) are returned."""
689 msg
= "os.popen3 is deprecated. Use the subprocess module."
690 warnings
.warn(msg
, DeprecationWarning, stacklevel
=2)
693 PIPE
= subprocess
.PIPE
694 p
= subprocess
.Popen(cmd
, shell
=True, bufsize
=bufsize
,
695 stdin
=PIPE
, stdout
=PIPE
, stderr
=PIPE
,
697 return p
.stdin
, p
.stdout
, p
.stderr
698 __all__
.append("popen3")
700 if not _exists("popen4"):
701 def popen4(cmd
, mode
="t", bufsize
=-1):
702 """Execute the shell command 'cmd' in a sub-process. On UNIX, 'cmd'
703 may be a sequence, in which case arguments will be passed directly to
704 the program without shell intervention (as with os.spawnv()). If 'cmd'
705 is a string it will be passed to the shell (as with os.system()). If
706 'bufsize' is specified, it sets the buffer size for the I/O pipes. The
707 file objects (child_stdin, child_stdout_stderr) are returned."""
709 msg
= "os.popen4 is deprecated. Use the subprocess module."
710 warnings
.warn(msg
, DeprecationWarning, stacklevel
=2)
713 PIPE
= subprocess
.PIPE
714 p
= subprocess
.Popen(cmd
, shell
=True, bufsize
=bufsize
,
715 stdin
=PIPE
, stdout
=PIPE
,
716 stderr
=subprocess
.STDOUT
, close_fds
=True)
717 return p
.stdin
, p
.stdout
718 __all__
.append("popen4")
720 import copy_reg
as _copy_reg
722 def _make_stat_result(tup
, dict):
723 return stat_result(tup
, dict)
725 def _pickle_stat_result(sr
):
726 (type, args
) = sr
.__reduce
__()
727 return (_make_stat_result
, args
)
730 _copy_reg
.pickle(stat_result
, _pickle_stat_result
, _make_stat_result
)
731 except NameError: # stat_result may not exist
734 def _make_statvfs_result(tup
, dict):
735 return statvfs_result(tup
, dict)
737 def _pickle_statvfs_result(sr
):
738 (type, args
) = sr
.__reduce
__()
739 return (_make_statvfs_result
, args
)
742 _copy_reg
.pickle(statvfs_result
, _pickle_statvfs_result
,
743 _make_statvfs_result
)
744 except NameError: # statvfs_result may not exist
747 if not _exists("urandom"):
751 Return a string of n random bytes suitable for cryptographic use.
755 _urandomfd
= open("/dev/urandom", O_RDONLY
)
756 except (OSError, IOError):
757 raise NotImplementedError("/dev/urandom (or equivalent) not found")
759 while len(bytes
) < n
:
760 bytes
+= read(_urandomfd
, n
- len(bytes
))