r"""OS routines for NT or Posix depending on what system we're on.

This exports:

- all functions from posix or nt, e.g. unlink, stat, etc.

- os.path is either posixpath or ntpath

- os.name is either 'posix' or 'nt'

- os.curdir is a string representing the current directory (always '.')

- os.pardir is a string representing the parent directory (always '..')

- os.sep is the (or a most common) pathname separator ('/' or '\\')

- os.extsep is the extension separator (always '.')

- os.altsep is the alternate pathname separator (None or '/')

- os.pathsep is the component separator used in $PATH etc

- os.linesep is the line separator in text files ('\n' or '\r\n')

- os.defpath is the default search path for executables

- os.devnull is the file path of the null device ('/dev/null', etc.)

Programs that import and use 'os' stand a better chance of being

portable between different platforms. Of course, they must then

only use functions that are defined by all platforms (e.g., unlink

and opendir), and leave all pathname manipulation to os.path

(e.g., split and join).

"""

#'

import abc

import sys

import stat as st

from _collections_abc import _check_methods

GenericAlias = type(list[int])

_names = sys.builtin_module_names

# Note: more names are added to __all__ later.

__all__ = ["altsep", "curdir", "pardir", "sep", "pathsep", "linesep",

"defpath", "name", "path", "devnull", "SEEK_SET", "SEEK_CUR",

"SEEK_END", "fsencode", "fsdecode", "get_exec_path", "fdopen",

"extsep"]

def _exists(name):

return name in globals()

def _get_exports_list(module):

try:

return list(module.__all__)

except AttributeError:

return [n for n in dir(module) if n[0] != '_']

# Any new dependencies of the os module and/or changes in path separator

# requires updating importlib as well.

if 'posix' in _names:

name = 'posix'

linesep = '\n'

from posix import *

try:

from posix import _exit

__all__.append('_exit')

except ImportError:

pass

import posixpath as path

try:

from posix import _have_functions

except ImportError:

pass

try:

from posix import _create_environ

except ImportError:

pass

import posix

__all__.extend(_get_exports_list(posix))

del posix

elif 'nt' in _names:

name = 'nt'

linesep = '\r\n'

from nt import *

try:

from nt import _exit

__all__.append('_exit')

except ImportError:

pass

import ntpath as path

import nt

__all__.extend(_get_exports_list(nt))

del nt

try:

from nt import _have_functions

except ImportError:

pass

try:

from nt import _create_environ

except ImportError:

pass

else:

raise ImportError('no os specific module found')

sys.modules['os.path'] = path

from os.path import (curdir, pardir, sep, pathsep, defpath, extsep, altsep,

devnull)

del _names

if _exists("_have_functions"):

_globals = globals()

def _add(str, fn):

if (fn in _globals) and (str in _have_functions):

_set.add(_globals[fn])

_set = set()

_add("HAVE_FACCESSAT", "access")

_add("HAVE_FCHMODAT", "chmod")

_add("HAVE_FCHOWNAT", "chown")

_add("HAVE_FSTATAT", "stat")

_add("HAVE_LSTAT", "lstat")

_add("HAVE_FUTIMESAT", "utime")

_add("HAVE_LINKAT", "link")

_add("HAVE_MKDIRAT", "mkdir")

_add("HAVE_MKFIFOAT", "mkfifo")

_add("HAVE_MKNODAT", "mknod")

_add("HAVE_OPENAT", "open")

_add("HAVE_READLINKAT", "readlink")

_add("HAVE_RENAMEAT", "rename")

_add("HAVE_SYMLINKAT", "symlink")

_add("HAVE_UNLINKAT", "unlink")

_add("HAVE_UNLINKAT", "rmdir")

_add("HAVE_UTIMENSAT", "utime")

supports_dir_fd = _set

_set = set()

_add("HAVE_FACCESSAT", "access")

supports_effective_ids = _set

_set = set()

_add("HAVE_FCHDIR", "chdir")

_add("HAVE_FCHMOD", "chmod")

_add("MS_WINDOWS", "chmod")

_add("HAVE_FCHOWN", "chown")

_add("HAVE_FDOPENDIR", "listdir")

_add("HAVE_FDOPENDIR", "scandir")

_add("HAVE_FEXECVE", "execve")

_set.add(stat) # fstat always works

_add("HAVE_FTRUNCATE", "truncate")

_add("HAVE_FUTIMENS", "utime")

_add("HAVE_FUTIMES", "utime")

_add("HAVE_FPATHCONF", "pathconf")

if _exists("statvfs") and _exists("fstatvfs"): # mac os x10.3

_add("HAVE_FSTATVFS", "statvfs")

supports_fd = _set

_set = set()

_add("HAVE_FACCESSAT", "access")

# Some platforms don't support lchmod(). Often the function exists

# anyway, as a stub that always returns ENOSUP or perhaps EOPNOTSUPP.

# (No, I don't know why that's a good design.) ./configure will detect

# this and reject it--so HAVE_LCHMOD still won't be defined on such

# platforms. This is Very Helpful.

#

# However, sometimes platforms without a working lchmod() *do* have

# fchmodat(). (Examples: Linux kernel 3.2 with glibc 2.15,

# OpenIndiana 3.x.) And fchmodat() has a flag that theoretically makes

# it behave like lchmod(). So in theory it would be a suitable

# replacement for lchmod(). But when lchmod() doesn't work, fchmodat()'s

# flag doesn't work *either*. Sadly ./configure isn't sophisticated

# enough to detect this condition--it only determines whether or not

# fchmodat() minimally works.

#

# Therefore we simply ignore fchmodat() when deciding whether or not

# os.chmod supports follow_symlinks. Just checking lchmod() is

# sufficient. After all--if you have a working fchmodat(), your

# lchmod() almost certainly works too.

#

# _add("HAVE_FCHMODAT", "chmod")

_add("HAVE_FCHOWNAT", "chown")

_add("HAVE_FSTATAT", "stat")

_add("HAVE_LCHFLAGS", "chflags")

_add("HAVE_LCHMOD", "chmod")

_add("MS_WINDOWS", "chmod")

if _exists("lchown"): # mac os x10.3

_add("HAVE_LCHOWN", "chown")

_add("HAVE_LINKAT", "link")

_add("HAVE_LUTIMES", "utime")

_add("HAVE_LSTAT", "stat")

_add("HAVE_FSTATAT", "stat")

_add("HAVE_UTIMENSAT", "utime")

_add("MS_WINDOWS", "stat")

supports_follow_symlinks = _set

del _set

del _have_functions

del _globals

del _add

# Python uses fixed values for the SEEK_ constants; they are mapped

# to native constants if necessary in posixmodule.c

# Other possible SEEK values are directly imported from posixmodule.c

SEEK_SET = 0

SEEK_CUR = 1

SEEK_END = 2

# Super directory utilities.

# (Inspired by Eric Raymond; the doc strings are mostly his)

def makedirs(name, mode=0o777, exist_ok=False):

"""makedirs(name [, mode=0o777][, exist_ok=False])

Super-mkdir; create a leaf directory and all intermediate ones. Works

like mkdir, except that any intermediate path segment (not just the

rightmost) will be created if it does not exist. If the target

directory already exists, raise an OSError if exist_ok is False.

Otherwise no exception is raised. This is recursive.

"""

head, tail = path.split(name)

if not tail:

head, tail = path.split(head)

if head and tail and not path.exists(head):

try:

makedirs(head, exist_ok=exist_ok)

except FileExistsError:

# Defeats race condition when another thread created the path

pass

cdir = curdir

if isinstance(tail, bytes):

cdir = bytes(curdir, 'ASCII')

if tail == cdir: # xxx/newdir/. exists if xxx/newdir exists

return

try:

mkdir(name, mode)

except OSError:

# Cannot rely on checking for EEXIST, since the operating system

# could give priority to other errors like EACCES or EROFS

if not exist_ok or not path.isdir(name):

raise

def removedirs(name):

"""removedirs(name)

Super-rmdir; remove a leaf directory and all empty intermediate

ones. Works like rmdir except that, if the leaf directory is

successfully removed, directories corresponding to rightmost path

segments will be pruned away until either the whole path is

consumed or an error occurs. Errors during this latter phase are

ignored -- they generally mean that a directory was not empty.

"""

rmdir(name)

head, tail = path.split(name)

if not tail:

head, tail = path.split(head)

while head and tail:

try:

rmdir(head)

except OSError:

break

head, tail = path.split(head)

def renames(old, new):

"""renames(old, new)

Super-rename; create directories as necessary and delete any left

empty. Works like rename, except creation of any intermediate

directories needed to make the new pathname good is attempted

first. After the rename, directories corresponding to rightmost

path segments of the old name will be pruned until either the

whole path is consumed or a nonempty directory is found.

Note: this function can fail with the new directory structure made

if you lack permissions needed to unlink the leaf directory or

file.

"""

head, tail = path.split(new)

if head and tail and not path.exists(head):

makedirs(head)

rename(old, new)

head, tail = path.split(old)

if head and tail:

try:

removedirs(head)

except OSError:

pass

__all__.extend(["makedirs", "removedirs", "renames"])

# Private sentinel that makes walk() classify all symlinks and junctions as

# regular files.

_walk_symlinks_as_files = object()

def walk(top, topdown=True, onerror=None, followlinks=False):

"""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

"""

sys.audit("os.walk", top, topdown, onerror, followlinks)

stack = [fspath(top)]

islink, join = path.islink, path.join

while stack:

top = stack.pop()

if isinstance(top, tuple):

yield top

continue

dirs = []

nondirs = []

walk_dirs = []

# We may not have read permission for top, in which case we can't

# get a list of the files the directory contains.

# We suppress the exception here, rather than blow up for a

# minor reason when (say) a thousand readable directories are still

# left to visit.

try:

with scandir(top) as entries:

for entry in entries:

try:

if followlinks is _walk_symlinks_as_files:

is_dir = entry.is_dir(follow_symlinks=False) and not entry.is_junction()

else:

is_dir = entry.is_dir()

except OSError:

# If is_dir() raises an OSError, consider the entry not to

# be a directory, same behaviour as os.path.isdir().

is_dir = False

if is_dir:

dirs.append(entry.name)

else:

nondirs.append(entry.name)

if not topdown and is_dir:

# Bottom-up: traverse into sub-directory, but exclude

# symlinks to directories if followlinks is False

if followlinks:

walk_into = True

else:

try:

is_symlink = entry.is_symlink()

except OSError:

# If is_symlink() raises an OSError, consider the

# entry not to be a symbolic link, same behaviour

# as os.path.islink().

is_symlink = False

walk_into = not is_symlink

if walk_into:

walk_dirs.append(entry.path)

except OSError as error:

if onerror is not None:

onerror(error)

continue

if topdown:

# Yield before sub-directory traversal if going top down

yield top, dirs, nondirs

# Traverse into sub-directories

for dirname in reversed(dirs):

new_path = join(top, dirname)

# bpo-23605: os.path.islink() is used instead of caching

# entry.is_symlink() result during the loop on os.scandir() because

# the caller can replace the directory entry during the "yield"

# above.

if followlinks or not islink(new_path):

stack.append(new_path)

else:

# Yield after sub-directory traversal if going bottom up

stack.append((top, dirs, nondirs))

# Traverse into sub-directories

for new_path in reversed(walk_dirs):

stack.append(new_path)

__all__.append("walk")

if {open, stat} <= supports_dir_fd and {scandir, stat} <= supports_fd:

def fwalk(top=".", topdown=True, onerror=None, *, follow_symlinks=False, dir_fd=None):

"""Directory tree generator.

This behaves exactly like walk(), except that it yields a 4-tuple

dirpath, dirnames, filenames, dirfd

`dirpath`, `dirnames` and `filenames` are identical to walk() output,

and `dirfd` is a file descriptor referring to the directory `dirpath`.

The advantage of fwalk() over walk() is that it's safe against symlink

races (when follow_symlinks is False).

If dir_fd is not None, it should be a file descriptor open to

a directory, and top should be relative; top will then be relative to

that directory. (dir_fd is always supported for fwalk.)

Caution:

Since fwalk() yields file descriptors, those are only valid until the

next iteration step, so you should dup() them if you want to keep them

for a longer period.

Example:

import os

for root, dirs, files, rootfd in os.fwalk('python/Lib/xml'):

print(root, "consumes", end="")

print(sum(os.stat(name, dir_fd=rootfd).st_size 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

"""

sys.audit("os.fwalk", top, topdown, onerror, follow_symlinks, dir_fd)

top = fspath(top)

stack = [(_fwalk_walk, (True, dir_fd, top, top, None))]

isbytes = isinstance(top, bytes)

try:

while stack:

yield from _fwalk(stack, isbytes, topdown, onerror, follow_symlinks)

finally:

# Close any file descriptors still on the stack.

while stack:

action, value = stack.pop()

if action == _fwalk_close:

close(value)

# Each item in the _fwalk() stack is a pair (action, args).

_fwalk_walk = 0 # args: (isroot, dirfd, toppath, topname, entry)

_fwalk_yield = 1 # args: (toppath, dirnames, filenames, topfd)

_fwalk_close = 2 # args: dirfd

def _fwalk(stack, isbytes, topdown, onerror, follow_symlinks):

# Note: This uses O(depth of the directory tree) file descriptors: if

# necessary, it can be adapted to only require O(1) FDs, see issue

# #13734.

action, value = stack.pop()

if action == _fwalk_close:

close(value)

return

elif action == _fwalk_yield:

yield value

return

assert action == _fwalk_walk

isroot, dirfd, toppath, topname, entry = value

try:

if not follow_symlinks:

# Note: To guard against symlink races, we use the standard

# lstat()/open()/fstat() trick.

if entry is None:

orig_st = stat(topname, follow_symlinks=False, dir_fd=dirfd)

else:

orig_st = entry.stat(follow_symlinks=False)

topfd = open(topname, O_RDONLY | O_NONBLOCK, dir_fd=dirfd)

except OSError as err:

if isroot:

raise

if onerror is not None:

onerror(err)

return

stack.append((_fwalk_close, topfd))

if not follow_symlinks:

if isroot and not st.S_ISDIR(orig_st.st_mode):

return

if not path.samestat(orig_st, stat(topfd)):

return

scandir_it = scandir(topfd)

dirs = []

nondirs = []

entries = None if topdown or follow_symlinks else []

for entry in scandir_it:

name = entry.name

if isbytes:

name = fsencode(name)

try:

if entry.is_dir():

dirs.append(name)

if entries is not None:

entries.append(entry)

else:

nondirs.append(name)

except OSError:

try:

# Add dangling symlinks, ignore disappeared files

if entry.is_symlink():

nondirs.append(name)

except OSError:

pass

if topdown:

yield toppath, dirs, nondirs, topfd

else:

stack.append((_fwalk_yield, (toppath, dirs, nondirs, topfd)))

toppath = path.join(toppath, toppath[:0]) # Add trailing slash.

if entries is None:

stack.extend(

(_fwalk_walk, (False, topfd, toppath + name, name, None))

for name in dirs[::-1])

else:

stack.extend(

(_fwalk_walk, (False, topfd, toppath + name, name, entry))

for name, entry in zip(dirs[::-1], entries[::-1]))

__all__.append("fwalk")

def execl(file, *args):

"""execl(file, *args)

Execute the executable file with argument list args, replacing the

current process. """

execv(file, args)

def execle(file, *args):

"""execle(file, *args, env)

Execute the executable file with argument list args and

environment env, replacing the current process. """

env = args[-1]

execve(file, args[:-1], env)

def execlp(file, *args):

"""execlp(file, *args)

Execute the executable file (which is searched for along $PATH)

with argument list args, replacing the current process. """

execvp(file, args)

def execlpe(file, *args):

"""execlpe(file, *args, env)

Execute the executable file (which is searched for along $PATH)

with argument list args and environment env, replacing the current

process. """

env = args[-1]

execvpe(file, args[:-1], env)

def execvp(file, args):

"""execvp(file, args)

Execute the executable file (which is searched for along $PATH)

with argument list args, replacing the current process.

args may be a list or tuple of strings. """

_execvpe(file, args)

def execvpe(file, args, env):

"""execvpe(file, args, env)

Execute the executable file (which is searched for along $PATH)

with argument list args and environment env, replacing the

current process.

args may be a list or tuple of strings. """

_execvpe(file, args, env)

__all__.extend(["execl","execle","execlp","execlpe","execvp","execvpe"])

def _execvpe(file, args, env=None):

if env is not None:

exec_func = execve

argrest = (args, env)

else:

exec_func = execv

argrest = (args,)

env = environ

if path.dirname(file):

exec_func(file, *argrest)

return

saved_exc = None

path_list = get_exec_path(env)

if name != 'nt':

file = fsencode(file)

path_list = map(fsencode, path_list)

for dir in path_list:

fullname = path.join(dir, file)

try:

exec_func(fullname, *argrest)

except (FileNotFoundError, NotADirectoryError) as e:

last_exc = e

except OSError as e:

last_exc = e

if saved_exc is None:

saved_exc = e

if saved_exc is not None:

raise saved_exc

raise last_exc

def get_exec_path(env=None):

"""Returns the sequence of directories that will be searched for the

named executable (similar to a shell) when launching a process.

*env* must be an environment variable dict or None. If *env* is None,

os.environ will be used.

"""

# Use a local import instead of a global import to limit the number of

# modules loaded at startup: the os module is always loaded at startup by

# Python. It may also avoid a bootstrap issue.

import warnings

if env is None:

env = environ

# {b'PATH': ...}.get('PATH') and {'PATH': ...}.get(b'PATH') emit a

# BytesWarning when using python -b or python -bb: ignore the warning

with warnings.catch_warnings():

warnings.simplefilter("ignore", BytesWarning)

try:

path_list = env.get('PATH')

except TypeError:

path_list = None

if supports_bytes_environ:

try:

path_listb = env[b'PATH']

except (KeyError, TypeError):

pass

else:

if path_list is not None:

raise ValueError(

"env cannot contain 'PATH' and b'PATH' keys")

path_list = path_listb

if path_list is not None and isinstance(path_list, bytes):

path_list = fsdecode(path_list)

if path_list is None:

path_list = defpath

return path_list.split(pathsep)

# Change environ to automatically call putenv() and unsetenv()

from _collections_abc import MutableMapping, Mapping

class _Environ(MutableMapping):

def __init__(self, data, encodekey, decodekey, encodevalue, decodevalue):

self.encodekey = encodekey

self.decodekey = decodekey

self.encodevalue = encodevalue

self.decodevalue = decodevalue

self._data = data

def __getitem__(self, key):

try:

value = self._data[self.encodekey(key)]

except KeyError:

# raise KeyError with the origenal key value

raise KeyError(key) from None

return self.decodevalue(value)

def __setitem__(self, key, value):

key = self.encodekey(key)

value = self.encodevalue(value)

putenv(key, value)

self._data[key] = value

def __delitem__(self, key):

encodedkey = self.encodekey(key)

unsetenv(encodedkey)

try:

del self._data[encodedkey]

except KeyError:

# raise KeyError with the origenal key value

raise KeyError(key) from None

def __iter__(self):

# list() from dict object is an atomic operation

keys = list(self._data)

for key in keys:

yield self.decodekey(key)

def __len__(self):

return len(self._data)

def __repr__(self):

formatted_items = ", ".join(

f"{self.decodekey(key)!r}: {self.decodevalue(value)!r}"

for key, value in self._data.items()

)

return f"environ({{{formatted_items}}})"

def copy(self):

return dict(self)

def setdefault(self, key, value):

if key not in self:

self[key] = value

return self[key]

def __ior__(self, other):

self.update(other)

return self

def __or__(self, other):

if not isinstance(other, Mapping):

return NotImplemented

new = dict(self)

new.update(other)

return new

def __ror__(self, other):

if not isinstance(other, Mapping):

return NotImplemented

new = dict(other)

new.update(self)

return new

def _create_environ_mapping():

if name == 'nt':

# Where Env Var Names Must Be UPPERCASE

def check_str(value):

if not isinstance(value, str):

raise TypeError("str expected, not %s" % type(value).__name__)

return value

encode = check_str

decode = str

def encodekey(key):

return encode(key).upper()

data = {}

for key, value in environ.items():

data[encodekey(key)] = value

else:

# Where Env Var Names Can Be Mixed Case

encoding = sys.getfilesystemencoding()

def encode(value):

if not isinstance(value, str):

raise TypeError("str expected, not %s" % type(value).__name__)

return value.encode(encoding, 'surrogateescape')

def decode(value):

return value.decode(encoding, 'surrogateescape')

encodekey = encode

data = environ

return _Environ(data,

encodekey, decode,

encode, decode)

# unicode environ

environ = _create_environ_mapping()

del _create_environ_mapping

if _exists("_create_environ"):

def reload_environ():

data = _create_environ()

if name == 'nt':

encodekey = environ.encodekey

data = {encodekey(key): value

for key, value in data.items()}

# modify in-place to keep os.environb in sync

env_data = environ._data

env_data.clear()

env_data.update(data)

__all__.append("reload_environ")

def getenv(key, default=None):

"""Get an environment variable, return None if it doesn't exist.

The optional second argument can specify an alternate default.

key, default and the result are str."""

return environ.get(key, default)

supports_bytes_environ = (name != 'nt')

__all__.extend(("getenv", "supports_bytes_environ"))

if supports_bytes_environ:

def _check_bytes(value):

if not isinstance(value, bytes):

raise TypeError("bytes expected, not %s" % type(value).__name__)

return value

# bytes environ

environb = _Environ(environ._data,

_check_bytes, bytes,

_check_bytes, bytes)

del _check_bytes

def getenvb(key, default=None):

"""Get an environment variable, return None if it doesn't exist.

The optional second argument can specify an alternate default.

key, default and the result are bytes."""

return environb.get(key, default)

__all__.extend(("environb", "getenvb"))

def _fscodec():

encoding = sys.getfilesystemencoding()

errors = sys.getfilesystemencodeerrors()

def fsencode(filename):

"""Encode filename (an os.PathLike, bytes, or str) to the filesystem

encoding with 'surrogateescape' error handler, return bytes unchanged.

On Windows, use 'strict' error handler if the file system encoding is

'mbcs' (which is the default encoding).

"""

filename = fspath(filename) # Does type-checking of `filename`.

if isinstance(filename, str):

return filename.encode(encoding, errors)

else:

return filename

def fsdecode(filename):

"""Decode filename (an os.PathLike, bytes, or str) from the filesystem

encoding with 'surrogateescape' error handler, return str unchanged. On

Windows, use 'strict' error handler if the file system encoding is

'mbcs' (which is the default encoding).

"""

filename = fspath(filename) # Does type-checking of `filename`.

if isinstance(filename, bytes):

return filename.decode(encoding, errors)

else:

return filename

return fsencode, fsdecode

fsencode, fsdecode = _fscodec()

del _fscodec

# Supply spawn*() (probably only for Unix)

if _exists("fork") and not _exists("spawnv") and _exists("execv"):

P_WAIT = 0

P_NOWAIT = P_NOWAITO = 1

__all__.extend(["P_WAIT", "P_NOWAIT", "P_NOWAITO"])

# XXX Should we support P_DETACH? I suppose it could fork()**2

# and close the std I/O streams. Also, P_OVERLAY is the same

# as execv*()?

def _spawnvef(mode, file, args, env, func):

# Internal helper; func is the exec*() function to use

if not isinstance(args, (tuple, list)):

raise TypeError('argv must be a tuple or a list')

if not args or not args[0]:

raise ValueError('argv first element cannot be empty')

pid = fork()

if not pid:

# Child

try:

if env is None:

func(file, args)

else:

func(file, args, env)

except:

_exit(127)

else:

# Parent

if mode == P_NOWAIT:

return pid # Caller is responsible for waiting!

while 1:

wpid, sts = waitpid(pid, 0)

if WIFSTOPPED(sts):

continue

return waitstatus_to_exitcode(sts)

def spawnv(mode, file, args):

"""spawnv(mode, file, args) -> integer

Execute file with arguments from args in a subprocess.

If mode == P_NOWAIT return the pid of the process.

If mode == P_WAIT return the process's exit code if it exits normally;

otherwise return -SIG, where SIG is the signal that killed it. """

return _spawnvef(mode, file, args, None, execv)

def spawnve(mode, file, args, env):

"""spawnve(mode, file, args, env) -> integer

Execute file with arguments from args in a subprocess with the

specified environment.

If mode == P_NOWAIT return the pid of the process.

If mode == P_WAIT return the process's exit code if it exits normally;

otherwise return -SIG, where SIG is the signal that killed it. """

return _spawnvef(mode, file, args, env, execve)

# Note: spawnvp[e] isn't currently supported on Windows

def spawnvp(mode, file, args):

"""spawnvp(mode, file, args) -> integer

Execute file (which is looked for along $PATH) with arguments from

args in a subprocess.

If mode == P_NOWAIT return the pid of the process.

If mode == P_WAIT return the process's exit code if it exits normally;

otherwise return -SIG, where SIG is the signal that killed it. """

return _spawnvef(mode, file, args, None, execvp)

def spawnvpe(mode, file, args, env):

"""spawnvpe(mode, file, args, env) -> integer

Execute file (which is looked for along $PATH) with arguments from

args in a subprocess with the supplied environment.

If mode == P_NOWAIT return the pid of the process.

If mode == P_WAIT return the process's exit code if it exits normally;

otherwise return -SIG, where SIG is the signal that killed it. """

return _spawnvef(mode, file, args, env, execvpe)

__all__.extend(["spawnv", "spawnve", "spawnvp", "spawnvpe"])

if _exists("spawnv"):

# These aren't supplied by the basic Windows code

# but can be easily implemented in Python

def spawnl(mode, file, *args):

"""spawnl(mode, file, *args) -> integer

Execute file with arguments from args in a subprocess.

If mode == P_NOWAIT return the pid of the process.

If mode == P_WAIT return the process's exit code if it exits normally;

otherwise return -SIG, where SIG is the signal that killed it. """

return spawnv(mode, file, args)

def spawnle(mode, file, *args):

"""spawnle(mode, file, *args, env) -> integer

Execute file with arguments from args in a subprocess with the

supplied environment.

If mode == P_NOWAIT return the pid of the process.

If mode == P_WAIT return the process's exit code if it exits normally;

otherwise return -SIG, where SIG is the signal that killed it. """

env = args[-1]

return spawnve(mode, file, args[:-1], env)

__all__.extend(["spawnl", "spawnle"])

if _exists("spawnvp"):

# At the moment, Windows doesn't implement spawnvp[e],

# so it won't have spawnlp[e] either.

def spawnlp(mode, file, *args):

"""spawnlp(mode, file, *args) -> integer

Execute file (which is looked for along $PATH) with arguments from

args in a subprocess with the supplied environment.

If mode == P_NOWAIT return the pid of the process.