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os

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 ('\r' or '\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).

Classes

DirEntry

inode(self, /)

  Return inode of the entry; cached per entry.

is_dir(self, /, *, follow_symlinks=True)

  Return True if the entry is a directory; cached per entry.

is_file(self, /, *, follow_symlinks=True)

  Return True if the entry is a file; cached per entry.

is_symlink(self, /)

  Return True if the entry is a symbolic link; cached per entry.

stat(self, /, *, follow_symlinks=True)

  Return stat_result object for the entry; cached per entry.

name = <member 'name' of 'posix.DirEntry' objects>
  the entry's base filename, relative to scandir() "path" argument

path = <member 'path' of 'posix.DirEntry' objects>
  the entry's full path name; equivalent to os.path.join(scandir_path, entry.name)

GenericAlias

Represent a PEP 585 generic type

E.g. for t = list[int], t.__origin__ is list and t.__args__ is (int,).

Mapping

get(self, key, default=None)

  D.get(k[,d]) -> D[k] if k in D, else d.  d defaults to None.

items(self)

  D.items() -> a set-like object providing a view on D's items

keys(self)

  D.keys() -> a set-like object providing a view on D's keys

values(self)

  D.values() -> an object providing a view on D's values

MutableMapping

clear(self)

  D.clear() -> None.  Remove all items from D.

get(self, key, default=None)

  D.get(k[,d]) -> D[k] if k in D, else d.  d defaults to None.

items(self)

  D.items() -> a set-like object providing a view on D's items

keys(self)

  D.keys() -> a set-like object providing a view on D's keys

pop(self, key, default=<object object at 0x7f0227c3c170>)

  D.pop(k[,d]) -> v, remove specified key and return the corresponding value.
            If key is not found, d is returned if given, otherwise KeyError is raised.
        

popitem(self)

  D.popitem() -> (k, v), remove and return some (key, value) pair
             as a 2-tuple; but raise KeyError if D is empty.
        

setdefault(self, key, default=None)

  D.setdefault(k[,d]) -> D.get(k,d), also set D[k]=d if k not in D

update(self, other=(), /, **kwds)

   D.update([E, ]**F) -> None.  Update D from mapping/iterable E and F.
              If E present and has a .keys() method, does:     for k in E: D[k] = E[k]
              If E present and lacks .keys() method, does:     for (k, v) in E: D[k] = v
              In either case, this is followed by: for k, v in F.items(): D[k] = v
        

values(self)

  D.values() -> an object providing a view on D's values

PathLike

Abstract base class for implementing the file system path protocol.

OSError

Base class for I/O related errors.

with_traceback(...)

  Exception.with_traceback(tb) --
      set self.__traceback__ to tb and return self.

args = <attribute 'args' of 'BaseException' objects>

characters_written = <attribute 'characters_written' of 'OSError' objects>

errno = <member 'errno' of 'OSError' objects>
  POSIX exception code

filename = <member 'filename' of 'OSError' objects>
  exception filename

filename2 = <member 'filename2' of 'OSError' objects>
  second exception filename

strerror = <member 'strerror' of 'OSError' objects>
  exception strerror

sched_param

Currently has only one field: sched_priority

  sched_priority
    A scheduling parameter.

count(self, value, /)

  Return number of occurrences of value.

index(self, value, start=0, stop=9223372036854775807, /)

  Return first index of value.

  Raises ValueError if the value is not present.

n_fields = 1

n_sequence_fields = 1

n_unnamed_fields = 0

sched_priority = <member 'sched_priority' of 'posix.sched_param' objects>
  the scheduling priority

stat_result

stat_result: Result from stat, fstat, or lstat.

This object may be accessed either as a tuple of
  (mode, ino, dev, nlink, uid, gid, size, atime, mtime, ctime)
or via the attributes st_mode, st_ino, st_dev, st_nlink, st_uid, and so on.

Posix/windows: If your platform supports st_blksize, st_blocks, st_rdev,
or st_flags, they are available as attributes only.

See os.stat for more information.

count(self, value, /)

  Return number of occurrences of value.

index(self, value, start=0, stop=9223372036854775807, /)

  Return first index of value.

  Raises ValueError if the value is not present.

n_fields = 19

n_sequence_fields = 10

n_unnamed_fields = 3

st_atime = <member 'st_atime' of 'os.stat_result' objects>
  time of last access

st_atime_ns = <member 'st_atime_ns' of 'os.stat_result' objects>
  time of last access in nanoseconds

st_blksize = <member 'st_blksize' of 'os.stat_result' objects>
  blocksize for filesystem I/O

st_blocks = <member 'st_blocks' of 'os.stat_result' objects>
  number of blocks allocated

st_ctime = <member 'st_ctime' of 'os.stat_result' objects>
  time of last change

st_ctime_ns = <member 'st_ctime_ns' of 'os.stat_result' objects>
  time of last change in nanoseconds

st_dev = <member 'st_dev' of 'os.stat_result' objects>
  device

st_gid = <member 'st_gid' of 'os.stat_result' objects>
  group ID of owner

st_ino = <member 'st_ino' of 'os.stat_result' objects>
  inode

st_mode = <member 'st_mode' of 'os.stat_result' objects>
  protection bits

st_mtime = <member 'st_mtime' of 'os.stat_result' objects>
  time of last modification

st_mtime_ns = <member 'st_mtime_ns' of 'os.stat_result' objects>
  time of last modification in nanoseconds

st_nlink = <member 'st_nlink' of 'os.stat_result' objects>
  number of hard links

st_rdev = <member 'st_rdev' of 'os.stat_result' objects>
  device type (if inode device)

st_size = <member 'st_size' of 'os.stat_result' objects>
  total size, in bytes

st_uid = <member 'st_uid' of 'os.stat_result' objects>
  user ID of owner

statvfs_result

statvfs_result: Result from statvfs or fstatvfs.

This object may be accessed either as a tuple of
  (bsize, frsize, blocks, bfree, bavail, files, ffree, favail, flag, namemax),
or via the attributes f_bsize, f_frsize, f_blocks, f_bfree, and so on.

See os.statvfs for more information.

count(self, value, /)

  Return number of occurrences of value.

index(self, value, start=0, stop=9223372036854775807, /)

  Return first index of value.

  Raises ValueError if the value is not present.

f_bavail = <member 'f_bavail' of 'os.statvfs_result' objects>

f_bfree = <member 'f_bfree' of 'os.statvfs_result' objects>

f_blocks = <member 'f_blocks' of 'os.statvfs_result' objects>

f_bsize = <member 'f_bsize' of 'os.statvfs_result' objects>

f_favail = <member 'f_favail' of 'os.statvfs_result' objects>

f_ffree = <member 'f_ffree' of 'os.statvfs_result' objects>

f_files = <member 'f_files' of 'os.statvfs_result' objects>

f_flag = <member 'f_flag' of 'os.statvfs_result' objects>

f_frsize = <member 'f_frsize' of 'os.statvfs_result' objects>

f_fsid = <member 'f_fsid' of 'os.statvfs_result' objects>

f_namemax = <member 'f_namemax' of 'os.statvfs_result' objects>

n_fields = 11

n_sequence_fields = 10

n_unnamed_fields = 0

terminal_size

A tuple of (columns, lines) for holding terminal window size

count(self, value, /)

  Return number of occurrences of value.

index(self, value, start=0, stop=9223372036854775807, /)

  Return first index of value.

  Raises ValueError if the value is not present.

columns = <member 'columns' of 'os.terminal_size' objects>
  width of the terminal window in characters

lines = <member 'lines' of 'os.terminal_size' objects>
  height of the terminal window in characters

n_fields = 2

n_sequence_fields = 2

n_unnamed_fields = 0

times_result

times_result: Result from os.times().

This object may be accessed either as a tuple of
  (user, system, children_user, children_system, elapsed),
or via the attributes user, system, children_user, children_system,
and elapsed.

See os.times for more information.

count(self, value, /)

  Return number of occurrences of value.

index(self, value, start=0, stop=9223372036854775807, /)

  Return first index of value.

  Raises ValueError if the value is not present.

children_system = <member 'children_system' of 'posix.times_result' objects>
  system time of children

children_user = <member 'children_user' of 'posix.times_result' objects>
  user time of children

elapsed = <member 'elapsed' of 'posix.times_result' objects>
  elapsed time since an arbitrary point in the past

n_fields = 5

n_sequence_fields = 5

n_unnamed_fields = 0

system = <member 'system' of 'posix.times_result' objects>
  system time

user = <member 'user' of 'posix.times_result' objects>
  user time

uname_result

uname_result: Result from os.uname().

This object may be accessed either as a tuple of
  (sysname, nodename, release, version, machine),
or via the attributes sysname, nodename, release, version, and machine.

See os.uname for more information.

count(self, value, /)

  Return number of occurrences of value.

index(self, value, start=0, stop=9223372036854775807, /)

  Return first index of value.

  Raises ValueError if the value is not present.

machine = <member 'machine' of 'posix.uname_result' objects>
  hardware identifier

n_fields = 5

n_sequence_fields = 5

n_unnamed_fields = 0

nodename = <member 'nodename' of 'posix.uname_result' objects>
  name of machine on network (implementation-defined)

release = <member 'release' of 'posix.uname_result' objects>
  operating system release

sysname = <member 'sysname' of 'posix.uname_result' objects>
  operating system name

version = <member 'version' of 'posix.uname_result' objects>
  operating system version

waitid_result

waitid_result: Result from waitid.

This object may be accessed either as a tuple of
  (si_pid, si_uid, si_signo, si_status, si_code),
or via the attributes si_pid, si_uid, and so on.

See os.waitid for more information.

count(self, value, /)

  Return number of occurrences of value.

index(self, value, start=0, stop=9223372036854775807, /)

  Return first index of value.

  Raises ValueError if the value is not present.

n_fields = 5

n_sequence_fields = 5

n_unnamed_fields = 0

si_code = <member 'si_code' of 'posix.waitid_result' objects>

si_pid = <member 'si_pid' of 'posix.waitid_result' objects>

si_signo = <member 'si_signo' of 'posix.waitid_result' objects>

si_status = <member 'si_status' of 'posix.waitid_result' objects>

si_uid = <member 'si_uid' of 'posix.waitid_result' objects>

Functions

WCOREDUMP

WCOREDUMP(status, /)

  Return True if the process returning status was dumped to a core file.

WEXITSTATUS

WEXITSTATUS(status)

  Return the process return code from status.

WIFCONTINUED

WIFCONTINUED(status)

  Return True if a particular process was continued from a job control stop.

  Return True if the process returning status was continued from a
  job control stop.

WIFEXITED

WIFEXITED(status)

  Return True if the process returning status exited via the exit() system call.

WIFSIGNALED

WIFSIGNALED(status)

  Return True if the process returning status was terminated by a signal.

WIFSTOPPED

WIFSTOPPED(status)

  Return True if the process returning status was stopped.

WSTOPSIG

WSTOPSIG(status)

  Return the signal that stopped the process that provided the status value.

WTERMSIG

WTERMSIG(status)

  Return the signal that terminated the process that provided the status value.

abort

abort()

  Abort the interpreter immediately.

  This function 'dumps core' or otherwise fails in the hardest way possible
  on the hosting operating system.  This function never returns.

access

access(path, mode, *, dir_fd=None, effective_ids=False, follow_symlinks=True)

  Use the real uid/gid to test for access to a path.

    path
      Path to be tested; can be string, bytes, or a path-like object.
    mode
      Operating-system mode bitfield.  Can be F_OK to test existence,
      or the inclusive-OR of R_OK, W_OK, and X_OK.
    dir_fd
      If not None, it should be a file descriptor open to a directory,
      and path should be relative; path will then be relative to that
      directory.
    effective_ids
      If True, access will use the effective uid/gid instead of
      the real uid/gid.
    follow_symlinks
      If False, and the last element of the path is a symbolic link,
      access will examine the symbolic link itself instead of the file
      the link points to.

  dir_fd, effective_ids, and follow_symlinks may not be implemented
    on your platform.  If they are unavailable, using them will raise a
    NotImplementedError.

  Note that most operations will use the effective uid/gid, therefore this
    routine can be used in a suid/sgid environment to test if the invoking user
    has the specified access to the path.

chdir

chdir(path)

  Change the current working directory to the specified path.

  path may always be specified as a string.
  On some platforms, path may also be specified as an open file descriptor.
    If this functionality is unavailable, using it raises an exception.

chmod

chmod(path, mode, *, dir_fd=None, follow_symlinks=True)

  Change the access permissions of a file.

    path
      Path to be modified.  May always be specified as a str, bytes, or a path-like object.
      On some platforms, path may also be specified as an open file descriptor.
      If this functionality is unavailable, using it raises an exception.
    mode
      Operating-system mode bitfield.
    dir_fd
      If not None, it should be a file descriptor open to a directory,
      and path should be relative; path will then be relative to that
      directory.
    follow_symlinks
      If False, and the last element of the path is a symbolic link,
      chmod will modify the symbolic link itself instead of the file
      the link points to.

  It is an error to use dir_fd or follow_symlinks when specifying path as
    an open file descriptor.
  dir_fd and follow_symlinks may not be implemented on your platform.
    If they are unavailable, using them will raise a NotImplementedError.

chown

chown(path, uid, gid, *, dir_fd=None, follow_symlinks=True)

  Change the owner and group id of path to the numeric uid and gid.\

    path
      Path to be examined; can be string, bytes, a path-like object, or open-file-descriptor int.
    dir_fd
      If not None, it should be a file descriptor open to a directory,
      and path should be relative; path will then be relative to that
      directory.
    follow_symlinks
      If False, and the last element of the path is a symbolic link,
      stat will examine the symbolic link itself instead of the file
      the link points to.

  path may always be specified as a string.
  On some platforms, path may also be specified as an open file descriptor.
    If this functionality is unavailable, using it raises an exception.
  If dir_fd is not None, it should be a file descriptor open to a directory,
    and path should be relative; path will then be relative to that directory.
  If follow_symlinks is False, and the last element of the path is a symbolic
    link, chown will modify the symbolic link itself instead of the file the
    link points to.
  It is an error to use dir_fd or follow_symlinks when specifying path as
    an open file descriptor.
  dir_fd and follow_symlinks may not be implemented on your platform.
    If they are unavailable, using them will raise a NotImplementedError.

chroot

chroot(path)

  Change root directory to path.

close

close(fd)

  Close a file descriptor.

closerange

closerange(fd_low, fd_high, /)

  Closes all file descriptors in [fd_low, fd_high), ignoring errors.

confstr

confstr(name, /)

  Return a string-valued system configuration variable.

copy_file_range

copy_file_range(src, dst, count, offset_src=None, offset_dst=None)

  Copy count bytes from one file descriptor to another.

    src
      Source file descriptor.
    dst
      Destination file descriptor.
    count
      Number of bytes to copy.
    offset_src
      Starting offset in src.
    offset_dst
      Starting offset in dst.

  If offset_src is None, then src is read from the current position;
  respectively for offset_dst.

cpu_count

cpu_count()

  Return the number of CPUs in the system; return None if indeterminable.

  This number is not equivalent to the number of CPUs the current process can
  use.  The number of usable CPUs can be obtained with
  ``len(os.sched_getaffinity(0))``

ctermid

ctermid()

  Return the name of the controlling terminal for this process.

device_encoding

device_encoding(fd)

  Return a string describing the encoding of a terminal's file descriptor.

  The file descriptor must be attached to a terminal.
  If the device is not a terminal, return None.

dup

dup(fd, /)

  Return a duplicate of a file descriptor.

dup2

dup2(fd, fd2, inheritable=True)

  Duplicate file descriptor.

execl

execl(file, *args)

  execl(file, *args)

      Execute the executable file with argument list args, replacing the
      current process. 

execle

execle(file, *args)

  execle(file, *args, env)

      Execute the executable file with argument list args and
      environment env, replacing the current process. 

execlp

execlp(file, *args)

  execlp(file, *args)

      Execute the executable file (which is searched for along $PATH)
      with argument list args, replacing the current process. 

execlpe

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. 

execv

execv(path, argv, /)

  Execute an executable path with arguments, replacing current process.

    path
      Path of executable file.
    argv
      Tuple or list of strings.

execve

execve(path, argv, env)

  Execute an executable path with arguments, replacing current process.

    path
      Path of executable file.
    argv
      Tuple or list of strings.
    env
      Dictionary of strings mapping to strings.

execvp

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

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. 

fchdir

fchdir(fd)

  Change to the directory of the given file descriptor.

  fd must be opened on a directory, not a file.
  Equivalent to os.chdir(fd).

fchmod

fchmod(fd, mode)

  Change the access permissions of the file given by file descriptor fd.

  Equivalent to os.chmod(fd, mode).

fchown

fchown(fd, uid, gid)

  Change the owner and group id of the file specified by file descriptor.

  Equivalent to os.chown(fd, uid, gid).

fdatasync

fdatasync(fd)

  Force write of fd to disk without forcing update of metadata.

fdopen

fdopen(fd, *args, **kwargs)

fork

fork()

  Fork a child process.

  Return 0 to child process and PID of child to parent process.

forkpty

forkpty()

  Fork a new process with a new pseudo-terminal as controlling tty.

  Returns a tuple of (pid, master_fd).
  Like fork(), return pid of 0 to the child process,
  and pid of child to the parent process.
  To both, return fd of newly opened pseudo-terminal.

fpathconf

fpathconf(fd, name, /)

  Return the configuration limit name for the file descriptor fd.

  If there is no limit, return -1.

fsdecode

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).
        

fsencode

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).
        

fspath

fspath(path)

  Return the file system path representation of the object.

  If the object is str or bytes, then allow it to pass through as-is. If the
  object defines __fspath__(), then return the result of that method. All other
  types raise a TypeError.

fstat

fstat(fd)

  Perform a stat system call on the given file descriptor.

  Like stat(), but for an open file descriptor.
  Equivalent to os.stat(fd).

fstatvfs

fstatvfs(fd, /)

  Perform an fstatvfs system call on the given fd.

  Equivalent to statvfs(fd).

fsync

fsync(fd)

  Force write of fd to disk.

ftruncate

ftruncate(fd, length, /)

  Truncate a file, specified by file descriptor, to a specific length.

fwalk

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/email'):
              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 'CVS' in dirs:
                  dirs.remove('CVS')  # don't visit CVS directories
        

get_blocking

get_blocking(fd, /)

  Get the blocking mode of the file descriptor.

  Return False if the O_NONBLOCK flag is set, True if the flag is cleared.

get_exec_path

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.
    

get_inheritable

get_inheritable(fd, /)

  Get the close-on-exe flag of the specified file descriptor.

get_terminal_size

get_terminal_size(...)

  Return the size of the terminal window as (columns, lines).

  The optional argument fd (default standard output) specifies
  which file descriptor should be queried.

  If the file descriptor is not connected to a terminal, an OSError
  is thrown.

  This function will only be defined if an implementation is
  available for this system.

  shutil.get_terminal_size is the high-level function which should
  normally be used, os.get_terminal_size is the low-level implementation.

getcwd

getcwd()

  Return a unicode string representing the current working directory.

getcwdb

getcwdb()

  Return a bytes string representing the current working directory.

getegid

getegid()

  Return the current process's effective group id.

getenv

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.

getenvb

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.

geteuid

geteuid()

  Return the current process's effective user id.

getgid

getgid()

  Return the current process's group id.

getgrouplist

getgrouplist(user, group, /)

  Returns a list of groups to which a user belongs.

    user
      username to lookup
    group
      base group id of the user

getgroups

getgroups()

  Return list of supplemental group IDs for the process.

getloadavg

getloadavg()

  Return average recent system load information.

  Return the number of processes in the system run queue averaged over
  the last 1, 5, and 15 minutes as a tuple of three floats.
  Raises OSError if the load average was unobtainable.

getlogin

getlogin()

  Return the actual login name.

getpgid

getpgid(pid)

  Call the system call getpgid(), and return the result.

getpgrp

getpgrp()

  Return the current process group id.

getpid

getpid()

  Return the current process id.

getppid

getppid()

  Return the parent's process id.

  If the parent process has already exited, Windows machines will still
  return its id; others systems will return the id of the 'init' process (1).

getpriority

getpriority(which, who)

  Return program scheduling priority.

getrandom

getrandom(size, flags=0)

  Obtain a series of random bytes.

getresgid

getresgid()

  Return a tuple of the current process's real, effective, and saved group ids.

getresuid

getresuid()

  Return a tuple of the current process's real, effective, and saved user ids.

getsid

getsid(pid, /)

  Call the system call getsid(pid) and return the result.

getuid

getuid()

  Return the current process's user id.

getxattr

getxattr(path, attribute, *, follow_symlinks=True)

  Return the value of extended attribute attribute on path.

  path may be either a string, a path-like object, or an open file descriptor.
  If follow_symlinks is False, and the last element of the path is a symbolic
    link, getxattr will examine the symbolic link itself instead of the file
    the link points to.

initgroups

initgroups(username, gid, /)

  Initialize the group access list.

  Call the system initgroups() to initialize the group access list with all of
  the groups of which the specified username is a member, plus the specified
  group id.

isatty

isatty(fd, /)

  Return True if the fd is connected to a terminal.

  Return True if the file descriptor is an open file descriptor
  connected to the slave end of a terminal.

kill

kill(pid, signal, /)

  Kill a process with a signal.

killpg

killpg(pgid, signal, /)

  Kill a process group with a signal.

lchown

lchown(path, uid, gid)

  Change the owner and group id of path to the numeric uid and gid.

  This function will not follow symbolic links.
  Equivalent to os.chown(path, uid, gid, follow_symlinks=False).

link

link(src, dst, *, src_dir_fd=None, dst_dir_fd=None, follow_symlinks=True)

  Create a hard link to a file.

  If either src_dir_fd or dst_dir_fd is not None, it should be a file
    descriptor open to a directory, and the respective path string (src or dst)
    should be relative; the path will then be relative to that directory.
  If follow_symlinks is False, and the last element of src is a symbolic
    link, link will create a link to the symbolic link itself instead of the
    file the link points to.
  src_dir_fd, dst_dir_fd, and follow_symlinks may not be implemented on your
    platform.  If they are unavailable, using them will raise a
    NotImplementedError.

listdir

listdir(path=None)

  Return a list containing the names of the files in the directory.

  path can be specified as either str, bytes, or a path-like object.  If path is bytes,
    the filenames returned will also be bytes; in all other circumstances
    the filenames returned will be str.
  If path is None, uses the path='.'.
  On some platforms, path may also be specified as an open file descriptor;\
    the file descriptor must refer to a directory.
    If this functionality is unavailable, using it raises NotImplementedError.

  The list is in arbitrary order.  It does not include the special
  entries '.' and '..' even if they are present in the directory.

listxattr

listxattr(path=None, *, follow_symlinks=True)

  Return a list of extended attributes on path.

  path may be either None, a string, a path-like object, or an open file descriptor.
  if path is None, listxattr will examine the current directory.
  If follow_symlinks is False, and the last element of the path is a symbolic
    link, listxattr will examine the symbolic link itself instead of the file
    the link points to.

lockf

lockf(fd, command, length, /)

  Apply, test or remove a POSIX lock on an open file descriptor.

    fd
      An open file descriptor.
    command
      One of F_LOCK, F_TLOCK, F_ULOCK or F_TEST.
    length
      The number of bytes to lock, starting at the current position.

lseek

lseek(fd, position, how, /)

  Set the position of a file descriptor.  Return the new position.

  Return the new cursor position in number of bytes
  relative to the beginning of the file.

lstat

lstat(path, *, dir_fd=None)

  Perform a stat system call on the given path, without following symbolic links.

  Like stat(), but do not follow symbolic links.
  Equivalent to stat(path, follow_symlinks=False).

major

major(device, /)

  Extracts a device major number from a raw device number.

makedev

makedev(major, minor, /)

  Composes a raw device number from the major and minor device numbers.

makedirs

makedirs(name, mode=511, 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.

    

memfd_create

memfd_create(name, flags=1)

minor

minor(device, /)

  Extracts a device minor number from a raw device number.

mkdir

mkdir(path, mode=511, *, dir_fd=None)

  Create a directory.

  If dir_fd is not None, it should be a file descriptor open to a directory,
    and path should be relative; path will then be relative to that directory.
  dir_fd may not be implemented on your platform.
    If it is unavailable, using it will raise a NotImplementedError.

  The mode argument is ignored on Windows.

mkfifo

mkfifo(path, mode=438, *, dir_fd=None)

  Create a "fifo" (a POSIX named pipe).

  If dir_fd is not None, it should be a file descriptor open to a directory,
    and path should be relative; path will then be relative to that directory.
  dir_fd may not be implemented on your platform.
    If it is unavailable, using it will raise a NotImplementedError.

mknod

mknod(path, mode=384, device=0, *, dir_fd=None)

  Create a node in the file system.

  Create a node in the file system (file, device special file or named pipe)
  at path.  mode specifies both the permissions to use and the
  type of node to be created, being combined (bitwise OR) with one of
  S_IFREG, S_IFCHR, S_IFBLK, and S_IFIFO.  If S_IFCHR or S_IFBLK is set on mode,
  device defines the newly created device special file (probably using
  os.makedev()).  Otherwise device is ignored.

  If dir_fd is not None, it should be a file descriptor open to a directory,
    and path should be relative; path will then be relative to that directory.
  dir_fd may not be implemented on your platform.
    If it is unavailable, using it will raise a NotImplementedError.

nice

nice(increment, /)

  Add increment to the priority of process and return the new priority.

open

open(path, flags, mode=511, *, dir_fd=None)

  Open a file for low level IO.  Returns a file descriptor (integer).

  If dir_fd is not None, it should be a file descriptor open to a directory,
    and path should be relative; path will then be relative to that directory.
  dir_fd may not be implemented on your platform.
    If it is unavailable, using it will raise a NotImplementedError.

openpty

openpty()

  Open a pseudo-terminal.

  Return a tuple of (master_fd, slave_fd) containing open file descriptors
  for both the master and slave ends.

pathconf

pathconf(path, name)

  Return the configuration limit name for the file or directory path.

  If there is no limit, return -1.
  On some platforms, path may also be specified as an open file descriptor.
    If this functionality is unavailable, using it raises an exception.

pidfd_open

pidfd_open(pid, flags=0)

  Return a file descriptor referring to the process *pid*.

  The descriptor can be used to perform process management without races and
  signals.

pipe

pipe()

  Create a pipe.

  Returns a tuple of two file descriptors:
    (read_fd, write_fd)

pipe2

pipe2(flags, /)

  Create a pipe with flags set atomically.

  Returns a tuple of two file descriptors:
    (read_fd, write_fd)

  flags can be constructed by ORing together one or more of these values:
  O_NONBLOCK, O_CLOEXEC.

popen

popen(cmd, mode='r', buffering=-1)

posix_fadvise

posix_fadvise(fd, offset, length, advice, /)

  Announce an intention to access data in a specific pattern.

  Announce an intention to access data in a specific pattern, thus allowing
  the kernel to make optimizations.
  The advice applies to the region of the file specified by fd starting at
  offset and continuing for length bytes.
  advice is one of POSIX_FADV_NORMAL, POSIX_FADV_SEQUENTIAL,
  POSIX_FADV_RANDOM, POSIX_FADV_NOREUSE, POSIX_FADV_WILLNEED, or
  POSIX_FADV_DONTNEED.

posix_fallocate

posix_fallocate(fd, offset, length, /)

  Ensure a file has allocated at least a particular number of bytes on disk.

  Ensure that the file specified by fd encompasses a range of bytes
  starting at offset bytes from the beginning and continuing for length bytes.

posix_spawn

posix_spawn(...)

  Execute the program specified by path in a new process.

    path
      Path of executable file.
    argv
      Tuple or list of strings.
    env
      Dictionary of strings mapping to strings.
    file_actions
      A sequence of file action tuples.
    setpgroup
      The pgroup to use with the POSIX_SPAWN_SETPGROUP flag.
    resetids
      If the value is `true` the POSIX_SPAWN_RESETIDS will be activated.
    setsid
      If the value is `true` the POSIX_SPAWN_SETSID or POSIX_SPAWN_SETSID_NP will be activated.
    setsigmask
      The sigmask to use with the POSIX_SPAWN_SETSIGMASK flag.
    setsigdef
      The sigmask to use with the POSIX_SPAWN_SETSIGDEF flag.
    scheduler
      A tuple with the scheduler policy (optional) and parameters.

posix_spawnp

posix_spawnp(...)

  Execute the program specified by path in a new process.

    path
      Path of executable file.
    argv
      Tuple or list of strings.
    env
      Dictionary of strings mapping to strings.
    file_actions
      A sequence of file action tuples.
    setpgroup
      The pgroup to use with the POSIX_SPAWN_SETPGROUP flag.
    resetids
      If the value is `True` the POSIX_SPAWN_RESETIDS will be activated.
    setsid
      If the value is `True` the POSIX_SPAWN_SETSID or POSIX_SPAWN_SETSID_NP will be activated.
    setsigmask
      The sigmask to use with the POSIX_SPAWN_SETSIGMASK flag.
    setsigdef
      The sigmask to use with the POSIX_SPAWN_SETSIGDEF flag.
    scheduler
      A tuple with the scheduler policy (optional) and parameters.

pread

pread(fd, length, offset, /)

  Read a number of bytes from a file descriptor starting at a particular offset.

  Read length bytes from file descriptor fd, starting at offset bytes from
  the beginning of the file.  The file offset remains unchanged.

preadv

preadv(fd, buffers, offset, flags=0, /)

  Reads from a file descriptor into a number of mutable bytes-like objects.

  Combines the functionality of readv() and pread(). As readv(), it will
  transfer data into each buffer until it is full and then move on to the next
  buffer in the sequence to hold the rest of the data. Its fourth argument,
  specifies the file offset at which the input operation is to be performed. It
  will return the total number of bytes read (which can be less than the total
  capacity of all the objects).

  The flags argument contains a bitwise OR of zero or more of the following flags:

  - RWF_HIPRI
  - RWF_NOWAIT

  Using non-zero flags requires Linux 4.6 or newer.

putenv

putenv(name, value, /)

  Change or add an environment variable.

pwrite

pwrite(fd, buffer, offset, /)

  Write bytes to a file descriptor starting at a particular offset.

  Write buffer to fd, starting at offset bytes from the beginning of
  the file.  Returns the number of bytes writte.  Does not change the
  current file offset.

pwritev

pwritev(fd, buffers, offset, flags=0, /)

  Writes the contents of bytes-like objects to a file descriptor at a given offset.

  Combines the functionality of writev() and pwrite(). All buffers must be a sequence
  of bytes-like objects. Buffers are processed in array order. Entire contents of first
  buffer is written before proceeding to second, and so on. The operating system may
  set a limit (sysconf() value SC_IOV_MAX) on the number of buffers that can be used.
  This function writes the contents of each object to the file descriptor and returns
  the total number of bytes written.

  The flags argument contains a bitwise OR of zero or more of the following flags:

  - RWF_DSYNC
  - RWF_SYNC

  Using non-zero flags requires Linux 4.7 or newer.

read

read(fd, length, /)

  Read from a file descriptor.  Returns a bytes object.

readlink

readlink(path, *, dir_fd=None)

  Return a string representing the path to which the symbolic link points.

  If dir_fd is not None, it should be a file descriptor open to a directory,
  and path should be relative; path will then be relative to that directory.

  dir_fd may not be implemented on your platform.  If it is unavailable,
  using it will raise a NotImplementedError.

readv

readv(fd, buffers, /)

  Read from a file descriptor fd into an iterable of buffers.

  The buffers should be mutable buffers accepting bytes.
  readv will transfer data into each buffer until it is full
  and then move on to the next buffer in the sequence to hold
  the rest of the data.

  readv returns the total number of bytes read,
  which may be less than the total capacity of all the buffers.

register_at_fork

register_at_fork(...)

  Register callables to be called when forking a new process.

    before
      A callable to be called in the parent before the fork() syscall.
    after_in_child
      A callable to be called in the child after fork().
    after_in_parent
      A callable to be called in the parent after fork().

  'before' callbacks are called in reverse order.
  'after_in_child' and 'after_in_parent' callbacks are called in order.

remove

remove(path, *, dir_fd=None)

  Remove a file (same as unlink()).

  If dir_fd is not None, it should be a file descriptor open to a directory,
    and path should be relative; path will then be relative to that directory.
  dir_fd may not be implemented on your platform.
    If it is unavailable, using it will raise a NotImplementedError.

removedirs

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.

    

removexattr

removexattr(path, attribute, *, follow_symlinks=True)

  Remove extended attribute attribute on path.

  path may be either a string, a path-like object, or an open file descriptor.
  If follow_symlinks is False, and the last element of the path is a symbolic
    link, removexattr will modify the symbolic link itself instead of the file
    the link points to.

rename

rename(src, dst, *, src_dir_fd=None, dst_dir_fd=None)

  Rename a file or directory.

  If either src_dir_fd or dst_dir_fd is not None, it should be a file
    descriptor open to a directory, and the respective path string (src or dst)
    should be relative; the path will then be relative to that directory.
  src_dir_fd and dst_dir_fd, may not be implemented on your platform.
    If they are unavailable, using them will raise a NotImplementedError.

renames

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.

    

replace

replace(src, dst, *, src_dir_fd=None, dst_dir_fd=None)

  Rename a file or directory, overwriting the destination.

  If either src_dir_fd or dst_dir_fd is not None, it should be a file
    descriptor open to a directory, and the respective path string (src or dst)
    should be relative; the path will then be relative to that directory.
  src_dir_fd and dst_dir_fd, may not be implemented on your platform.
    If they are unavailable, using them will raise a NotImplementedError.

rmdir

rmdir(path, *, dir_fd=None)

  Remove a directory.

  If dir_fd is not None, it should be a file descriptor open to a directory,
    and path should be relative; path will then be relative to that directory.
  dir_fd may not be implemented on your platform.
    If it is unavailable, using it will raise a NotImplementedError.

scandir

scandir(path=None)

  Return an iterator of DirEntry objects for given path.

  path can be specified as either str, bytes, or a path-like object.  If path
  is bytes, the names of yielded DirEntry objects will also be bytes; in
  all other circumstances they will be str.

  If path is None, uses the path='.'.

sched_get_priority_max

sched_get_priority_max(policy)

  Get the maximum scheduling priority for policy.

sched_get_priority_min

sched_get_priority_min(policy)

  Get the minimum scheduling priority for policy.

sched_getaffinity

sched_getaffinity(pid, /)

  Return the affinity of the process identified by pid (or the current process if zero).

  The affinity is returned as a set of CPU identifiers.

sched_getparam

sched_getparam(pid, /)

  Returns scheduling parameters for the process identified by pid.

  If pid is 0, returns parameters for the calling process.
  Return value is an instance of sched_param.

sched_getscheduler

sched_getscheduler(pid, /)

  Get the scheduling policy for the process identified by pid.

  Passing 0 for pid returns the scheduling policy for the calling process.

sched_rr_get_interval

sched_rr_get_interval(pid, /)

  Return the round-robin quantum for the process identified by pid, in seconds.

  Value returned is a float.

sched_setaffinity

sched_setaffinity(pid, mask, /)

  Set the CPU affinity of the process identified by pid to mask.

  mask should be an iterable of integers identifying CPUs.

sched_setparam

sched_setparam(pid, param, /)

  Set scheduling parameters for the process identified by pid.

  If pid is 0, sets parameters for the calling process.
  param should be an instance of sched_param.

sched_setscheduler

sched_setscheduler(pid, policy, param, /)

  Set the scheduling policy for the process identified by pid.

  If pid is 0, the calling process is changed.
  param is an instance of sched_param.

sched_yield

sched_yield()

  Voluntarily relinquish the CPU.

sendfile

sendfile(out_fd, in_fd, offset, count)

  Copy count bytes from file descriptor in_fd to file descriptor out_fd.

set_blocking

set_blocking(fd, blocking, /)

  Set the blocking mode of the specified file descriptor.

  Set the O_NONBLOCK flag if blocking is False,
  clear the O_NONBLOCK flag otherwise.

set_inheritable

set_inheritable(fd, inheritable, /)

  Set the inheritable flag of the specified file descriptor.

setegid

setegid(egid, /)

  Set the current process's effective group id.

seteuid

seteuid(euid, /)

  Set the current process's effective user id.

setgid

setgid(gid, /)

  Set the current process's group id.

setgroups

setgroups(groups, /)

  Set the groups of the current process to list.

setpgid

setpgid(pid, pgrp, /)

  Call the system call setpgid(pid, pgrp).

setpgrp

setpgrp()

  Make the current process the leader of its process group.

setpriority

setpriority(which, who, priority)

  Set program scheduling priority.

setregid

setregid(rgid, egid, /)

  Set the current process's real and effective group ids.

setresgid

setresgid(rgid, egid, sgid, /)

  Set the current process's real, effective, and saved group ids.

setresuid

setresuid(ruid, euid, suid, /)

  Set the current process's real, effective, and saved user ids.

setreuid

setreuid(ruid, euid, /)

  Set the current process's real and effective user ids.

setsid

setsid()

  Call the system call setsid().

setuid

setuid(uid, /)

  Set the current process's user id.

setxattr

setxattr(path, attribute, value, flags=0, *, follow_symlinks=True)

  Set extended attribute attribute on path to value.

  path may be either a string, a path-like object,  or an open file descriptor.
  If follow_symlinks is False, and the last element of the path is a symbolic
    link, setxattr will modify the symbolic link itself instead of the file
    the link points to.

spawnl

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. 

spawnle

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. 

spawnlp

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.
  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. 

spawnlpe

spawnlpe(mode, file, *args)

  spawnlpe(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. 

spawnv

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. 

spawnve

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. 

spawnvp

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. 

spawnvpe

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. 

stat

stat(path, *, dir_fd=None, follow_symlinks=True)

  Perform a stat system call on the given path.

    path
      Path to be examined; can be string, bytes, a path-like object or
      open-file-descriptor int.
    dir_fd
      If not None, it should be a file descriptor open to a directory,
      and path should be a relative string; path will then be relative to
      that directory.
    follow_symlinks
      If False, and the last element of the path is a symbolic link,
      stat will examine the symbolic link itself instead of the file
      the link points to.

  dir_fd and follow_symlinks may not be implemented
    on your platform.  If they are unavailable, using them will raise a
    NotImplementedError.

  It's an error to use dir_fd or follow_symlinks when specifying path as
    an open file descriptor.

statvfs

statvfs(path)

  Perform a statvfs system call on the given path.

  path may always be specified as a string.
  On some platforms, path may also be specified as an open file descriptor.
    If this functionality is unavailable, using it raises an exception.

strerror

strerror(code, /)

  Translate an error code to a message string.

symlink

symlink(src, dst, target_is_directory=False, *, dir_fd=None)

  Create a symbolic link pointing to src named dst.

  target_is_directory is required on Windows if the target is to be
    interpreted as a directory.  (On Windows, symlink requires
    Windows 6.0 or greater, and raises a NotImplementedError otherwise.)
    target_is_directory is ignored on non-Windows platforms.

  If dir_fd is not None, it should be a file descriptor open to a directory,
    and path should be relative; path will then be relative to that directory.
  dir_fd may not be implemented on your platform.
    If it is unavailable, using it will raise a NotImplementedError.

sync

sync()

  Force write of everything to disk.

sysconf

sysconf(name, /)

  Return an integer-valued system configuration variable.

system

system(command)

  Execute the command in a subshell.

tcgetpgrp

tcgetpgrp(fd, /)

  Return the process group associated with the terminal specified by fd.

tcsetpgrp

tcsetpgrp(fd, pgid, /)

  Set the process group associated with the terminal specified by fd.

times

times()

  Return a collection containing process timing information.

  The object returned behaves like a named tuple with these fields:
    (utime, stime, cutime, cstime, elapsed_time)
  All fields are floating point numbers.

truncate

truncate(path, length)

  Truncate a file, specified by path, to a specific length.

  On some platforms, path may also be specified as an open file descriptor.
    If this functionality is unavailable, using it raises an exception.

ttyname

ttyname(fd, /)

  Return the name of the terminal device connected to 'fd'.

    fd
      Integer file descriptor handle.

umask

umask(mask, /)

  Set the current numeric umask and return the previous umask.

uname

uname()

  Return an object identifying the current operating system.

  The object behaves like a named tuple with the following fields:
    (sysname, nodename, release, version, machine)

unlink

unlink(path, *, dir_fd=None)

  Remove a file (same as remove()).

  If dir_fd is not None, it should be a file descriptor open to a directory,
    and path should be relative; path will then be relative to that directory.
  dir_fd may not be implemented on your platform.
    If it is unavailable, using it will raise a NotImplementedError.

unsetenv

unsetenv(name, /)

  Delete an environment variable.

urandom

urandom(size, /)

  Return a bytes object containing random bytes suitable for cryptographic use.

utime

utime(...)

  Set the access and modified time of path.

  path may always be specified as a string.
  On some platforms, path may also be specified as an open file descriptor.
    If this functionality is unavailable, using it raises an exception.

  If times is not None, it must be a tuple (atime, mtime);
      atime and mtime should be expressed as float seconds since the epoch.
  If ns is specified, it must be a tuple (atime_ns, mtime_ns);
      atime_ns and mtime_ns should be expressed as integer nanoseconds
      since the epoch.
  If times is None and ns is unspecified, utime uses the current time.
  Specifying tuples for both times and ns is an error.

  If dir_fd is not None, it should be a file descriptor open to a directory,
    and path should be relative; path will then be relative to that directory.
  If follow_symlinks is False, and the last element of the path is a symbolic
    link, utime will modify the symbolic link itself instead of the file the
    link points to.
  It is an error to use dir_fd or follow_symlinks when specifying path
    as an open file descriptor.
  dir_fd and follow_symlinks may not be available on your platform.
    If they are unavailable, using them will raise a NotImplementedError.

wait

wait()

  Wait for completion of a child process.

  Returns a tuple of information about the child process:
      (pid, status)

wait3

wait3(options)

  Wait for completion of a child process.

  Returns a tuple of information about the child process:
    (pid, status, rusage)

wait4

wait4(pid, options)

  Wait for completion of a specific child process.

  Returns a tuple of information about the child process:
    (pid, status, rusage)

waitid

waitid(idtype, id, options, /)

  Returns the result of waiting for a process or processes.

    idtype
      Must be one of be P_PID, P_PGID or P_ALL.
    id
      The id to wait on.
    options
      Constructed from the ORing of one or more of WEXITED, WSTOPPED
      or WCONTINUED and additionally may be ORed with WNOHANG or WNOWAIT.

  Returns either waitid_result or None if WNOHANG is specified and there are
  no children in a waitable state.

waitpid

waitpid(pid, options, /)

  Wait for completion of a given child process.

  Returns a tuple of information regarding the child process:
      (pid, status)

  The options argument is ignored on Windows.

waitstatus_to_exitcode

waitstatus_to_exitcode(status)

  Convert a wait status to an exit code.

  On Unix:

  * If WIFEXITED(status) is true, return WEXITSTATUS(status).
  * If WIFSIGNALED(status) is true, return -WTERMSIG(status).
  * Otherwise, raise a ValueError.

  On Windows, return status shifted right by 8 bits.

  On Unix, if the process is being traced or if waitpid() was called with
  WUNTRACED option, the caller must first check if WIFSTOPPED(status) is true.
  This function must not be called if WIFSTOPPED(status) is true.

walk

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 (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/email'):
          print(root, "consumes", end="")
          print(sum(getsize(join(root, name)) for name in files), end="")
          print("bytes in", len(files), "non-directory files")
          if 'CVS' in dirs:
              dirs.remove('CVS')  # don't visit CVS directories

    

write

write(fd, data, /)

  Write a bytes object to a file descriptor.

writev

writev(fd, buffers, /)

  Iterate over buffers, and write the contents of each to a file descriptor.

  Returns the total number of bytes written.
  buffers must be a sequence of bytes-like objects.

Other members

CLD_CONTINUED = 6

CLD_DUMPED = 3

CLD_EXITED = 1

CLD_KILLED = 2

CLD_STOPPED = 5

CLD_TRAPPED = 4

EX_CANTCREAT = 73

EX_CONFIG = 78

EX_DATAERR = 65

EX_IOERR = 74

EX_NOHOST = 68

EX_NOINPUT = 66

EX_NOPERM = 77

EX_NOUSER = 67

EX_OK = 0

EX_OSERR = 71

EX_OSFILE = 72

EX_PROTOCOL = 76

EX_SOFTWARE = 70

EX_TEMPFAIL = 75

EX_UNAVAILABLE = 69

EX_USAGE = 64

F_LOCK = 1

F_OK = 0

F_TEST = 3

F_TLOCK = 2

F_ULOCK = 0

GRND_NONBLOCK = 1

GRND_RANDOM = 2

MFD_ALLOW_SEALING = 2

MFD_CLOEXEC = 1

MFD_HUGETLB = 4

MFD_HUGE_16GB = -2013265920

MFD_HUGE_16MB = 1610612736

MFD_HUGE_1GB = 2013265920

MFD_HUGE_1MB = 1342177280

MFD_HUGE_256MB = 1879048192

MFD_HUGE_2GB = 2080374784

MFD_HUGE_2MB = 1409286144

MFD_HUGE_32MB = 1677721600

MFD_HUGE_512KB = 1275068416

MFD_HUGE_512MB = 1946157056

MFD_HUGE_64KB = 1073741824

MFD_HUGE_8MB = 1543503872

MFD_HUGE_MASK = 63

MFD_HUGE_SHIFT = 26

NGROUPS_MAX = 65536

O_ACCMODE = 3

O_APPEND = 1024

O_ASYNC = 8192

O_CLOEXEC = 524288

O_CREAT = 64

O_DIRECT = 16384

O_DIRECTORY = 65536

O_DSYNC = 4096

O_EXCL = 128

O_LARGEFILE = 0

O_NDELAY = 2048

O_NOATIME = 262144

O_NOCTTY = 256

O_NOFOLLOW = 131072

O_NONBLOCK = 2048

O_PATH = 2097152

O_RDONLY = 0

O_RDWR = 2

O_RSYNC = 1052672

O_SYNC = 1052672

O_TMPFILE = 4259840

O_TRUNC = 512

O_WRONLY = 1

POSIX_FADV_DONTNEED = 4

POSIX_FADV_NOREUSE = 5

POSIX_FADV_NORMAL = 0

POSIX_FADV_RANDOM = 1

POSIX_FADV_SEQUENTIAL = 2

POSIX_FADV_WILLNEED = 3

POSIX_SPAWN_CLOSE = 1

POSIX_SPAWN_DUP2 = 2

POSIX_SPAWN_OPEN = 0

PRIO_PGRP = 1

PRIO_PROCESS = 0

PRIO_USER = 2

P_ALL = 0

P_NOWAIT = 1

P_NOWAITO = 1

P_PGID = 2

P_PID = 1

P_PIDFD = 3

P_WAIT = 0

RTLD_DEEPBIND = 8

RTLD_GLOBAL = 256

RTLD_LAZY = 1

RTLD_LOCAL = 0

RTLD_NODELETE = 4096

RTLD_NOLOAD = 4

RTLD_NOW = 2

RWF_DSYNC = 2

RWF_HIPRI = 1

RWF_NOWAIT = 8

RWF_SYNC = 4

R_OK = 4

SCHED_BATCH = 3

SCHED_FIFO = 1

SCHED_IDLE = 5

SCHED_OTHER = 0

SCHED_RESET_ON_FORK = 1073741824

SCHED_RR = 2

SEEK_CUR = 1

SEEK_DATA = 3

SEEK_END = 2

SEEK_HOLE = 4

SEEK_SET = 0

ST_APPEND = 256

ST_MANDLOCK = 64

ST_NOATIME = 1024

ST_NODEV = 4

ST_NODIRATIME = 2048

ST_NOEXEC = 8

ST_NOSUID = 2

ST_RDONLY = 1

ST_RELATIME = 4096

ST_SYNCHRONOUS = 16

ST_WRITE = 128

TMP_MAX = 238328

WCONTINUED = 8

WEXITED = 4

WNOHANG = 1

WNOWAIT = 16777216

WSTOPPED = 2

WUNTRACED = 2

W_OK = 2

XATTR_CREATE = 1

XATTR_REPLACE = 2

XATTR_SIZE_MAX = 65536

X_OK = 1

altsep = None

confstr_names = {'CS_GNU_LIBC_VERSION': 2, 'CS_GNU_LIBPTHREAD_VERSION': 3, 'CS_LFS64_CFLAGS': 1004, 'CS_LFS64_LDFLAGS': 1005, 'CS_LFS64_LIBS': 1006, 'CS_LFS64_LINTFLAGS': 1007, 'CS_LFS_CFLAGS': 1000, 'CS_LFS_LDFLAGS': 1001, 'CS_LFS_LIBS': 1002, 'CS_LFS_LINTFLAGS': 1003, 'CS_PATH': 0, 'CS_XBS5_ILP32_OFF32_CFLAGS': 1100, 'CS_XBS5_ILP32_OFF32_LDFLAGS': 1101, 'CS_XBS5_ILP32_OFF32_LIBS': 1102, 'CS_XBS5_ILP32_OFF32_LINTFLAGS': 1103, 'CS_XBS5_ILP32_OFFBIG_CFLAGS': 1104, 'CS_XBS5_ILP32_OFFBIG_LDFLAGS': 1105, 'CS_XBS5_ILP32_OFFBIG_LIBS': 1106, 'CS_XBS5_ILP32_OFFBIG_LINTFLAGS': 1107, 'CS_XBS5_LP64_OFF64_CFLAGS': 1108, 'CS_XBS5_LP64_OFF64_LDFLAGS': 1109, 'CS_XBS5_LP64_OFF64_LIBS': 1110, 'CS_XBS5_LP64_OFF64_LINTFLAGS': 1111, 'CS_XBS5_LPBIG_OFFBIG_CFLAGS': 1112, 'CS_XBS5_LPBIG_OFFBIG_LDFLAGS': 1113, 'CS_XBS5_LPBIG_OFFBIG_LIBS': 1114, 'CS_XBS5_LPBIG_OFFBIG_LINTFLAGS': 1115}

curdir = '.'

defpath = '/bin:/usr/bin'

devnull = '/dev/null'

environ = environ({'PYTHONNOUSERSITE': 'true', 'PWD': '/', 'LOGNAME': 'amethyst', 'SYSTEMD_EXEC_PID': '1623040', 'LANG': 'en_US.UTF-8', 'INVOCATION_ID': 'e9f2da78a34743508a504107ea6a61b1', 'USER': 'amethyst', 'TZDIR': '/nix/store/hcrw29p0rv8lkb31yb728kgna4nq1ydd-tzdata-2021c/share/zoneinfo', 'SHLVL': '0', 'LOCALE_ARCHIVE': '/nix/store/gfzp1a6ab4ffwg75bnrycwdrd7cqki1i-glibc-locales-2.33-117/lib/locale/locale-archive', 'STATE_DIRECTORY': '/var/lib/amethyst', 'JOURNAL_STREAM': '8:21393181', 'PATH': '/nix/store/cgxc3jz7idrb1wnb2lard9rvcx6aw2si-python3-3.9.6/bin:/nix/store/42a8c7fk04zjmk0ckvf6ljiggn0hmf4f-amethyst-0.0.1/bin:/nix/store/hg27yaca6208n03wps829lfnnc77jd15-python3-3.9.6-env/bin:/nix/store/jd1y449cf66yx5d1hwyjvc4562b1p1am-coreutils-9.0/bin:/nix/store/jjvw20r6pz3ff7pn91yhvfx8s7izsqan-findutils-4.8.0/bin:/nix/store/df3ff57sbkgbdhc4ar19zs4y0hrhggii-gnugrep-3.7/bin:/nix/store/bpg0ia8nkavzw7s66avi1f9nz72i1p3r-gnused-4.8/bin:/nix/store/w4my56mxgknxk5m0vilgizi37iyibmvb-systemd-249.7/bin:/nix/store/hg27yaca6208n03wps829lfnnc77jd15-python3-3.9.6-env/sbin:/nix/store/jd1y449cf66yx5d1hwyjvc4562b1p1am-coreutils-9.0/sbin:/nix/store/jjvw20r6pz3ff7pn91yhvfx8s7izsqan-findutils-4.8.0/sbin:/nix/store/df3ff57sbkgbdhc4ar19zs4y0hrhggii-gnugrep-3.7/sbin:/nix/store/bpg0ia8nkavzw7s66avi1f9nz72i1p3r-gnused-4.8/sbin:/nix/store/w4my56mxgknxk5m0vilgizi37iyibmvb-systemd-249.7/sbin'})

environb = environ({b'PYTHONNOUSERSITE': b'true', b'PWD': b'/', b'LOGNAME': b'amethyst', b'SYSTEMD_EXEC_PID': b'1623040', b'LANG': b'en_US.UTF-8', b'INVOCATION_ID': b'e9f2da78a34743508a504107ea6a61b1', b'USER': b'amethyst', b'TZDIR': b'/nix/store/hcrw29p0rv8lkb31yb728kgna4nq1ydd-tzdata-2021c/share/zoneinfo', b'SHLVL': b'0', b'LOCALE_ARCHIVE': b'/nix/store/gfzp1a6ab4ffwg75bnrycwdrd7cqki1i-glibc-locales-2.33-117/lib/locale/locale-archive', b'STATE_DIRECTORY': b'/var/lib/amethyst', b'JOURNAL_STREAM': b'8:21393181', b'PATH': b'/nix/store/cgxc3jz7idrb1wnb2lard9rvcx6aw2si-python3-3.9.6/bin:/nix/store/42a8c7fk04zjmk0ckvf6ljiggn0hmf4f-amethyst-0.0.1/bin:/nix/store/hg27yaca6208n03wps829lfnnc77jd15-python3-3.9.6-env/bin:/nix/store/jd1y449cf66yx5d1hwyjvc4562b1p1am-coreutils-9.0/bin:/nix/store/jjvw20r6pz3ff7pn91yhvfx8s7izsqan-findutils-4.8.0/bin:/nix/store/df3ff57sbkgbdhc4ar19zs4y0hrhggii-gnugrep-3.7/bin:/nix/store/bpg0ia8nkavzw7s66avi1f9nz72i1p3r-gnused-4.8/bin:/nix/store/w4my56mxgknxk5m0vilgizi37iyibmvb-systemd-249.7/bin:/nix/store/hg27yaca6208n03wps829lfnnc77jd15-python3-3.9.6-env/sbin:/nix/store/jd1y449cf66yx5d1hwyjvc4562b1p1am-coreutils-9.0/sbin:/nix/store/jjvw20r6pz3ff7pn91yhvfx8s7izsqan-findutils-4.8.0/sbin:/nix/store/df3ff57sbkgbdhc4ar19zs4y0hrhggii-gnugrep-3.7/sbin:/nix/store/bpg0ia8nkavzw7s66avi1f9nz72i1p3r-gnused-4.8/sbin:/nix/store/w4my56mxgknxk5m0vilgizi37iyibmvb-systemd-249.7/sbin'})

extsep = '.'

linesep = '\n'

name = 'posix'

pardir = '..'

pathconf_names = {'PC_ALLOC_SIZE_MIN': 18, 'PC_ASYNC_IO': 10, 'PC_CHOWN_RESTRICTED': 6, 'PC_FILESIZEBITS': 13, 'PC_LINK_MAX': 0, 'PC_MAX_CANON': 1, 'PC_MAX_INPUT': 2, 'PC_NAME_MAX': 3, 'PC_NO_TRUNC': 7, 'PC_PATH_MAX': 4, 'PC_PIPE_BUF': 5, 'PC_PRIO_IO': 11, 'PC_REC_INCR_XFER_SIZE': 14, 'PC_REC_MAX_XFER_SIZE': 15, 'PC_REC_MIN_XFER_SIZE': 16, 'PC_REC_XFER_ALIGN': 17, 'PC_SOCK_MAXBUF': 12, 'PC_SYMLINK_MAX': 19, 'PC_SYNC_IO': 9, 'PC_VDISABLE': 8}

pathsep = ':'

sep = '/'

supports_bytes_environ = True

supports_dir_fd = {<built-in function readlink>, <built-in function chmod>, <built-in function rename>, <built-in function unlink>, <built-in function access>, <built-in function open>, <built-in function rmdir>, <built-in function symlink>, <built-in function utime>, <built-in function link>, <built-in function stat>, <built-in function chown>, <built-in function mknod>, <built-in function mkdir>, <built-in function mkfifo>}

supports_effective_ids = {<built-in function access>}

supports_fd = {<built-in function chdir>, <built-in function chmod>, <built-in function listdir>, <built-in function execve>, <built-in function statvfs>, <built-in function pathconf>, <built-in function scandir>, <built-in function utime>, <built-in function stat>, <built-in function chown>, <built-in function truncate>}

supports_follow_symlinks = {<built-in function access>, <built-in function utime>, <built-in function link>, <built-in function stat>, <built-in function chown>}

sysconf_names = {'SC_2_CHAR_TERM': 95, 'SC_2_C_BIND': 47, 'SC_2_C_DEV': 48, 'SC_2_C_VERSION': 96, 'SC_2_FORT_DEV': 49, 'SC_2_FORT_RUN': 50, 'SC_2_LOCALEDEF': 52, 'SC_2_SW_DEV': 51, 'SC_2_UPE': 97, 'SC_2_VERSION': 46, 'SC_AIO_LISTIO_MAX': 23, 'SC_AIO_MAX': 24, 'SC_AIO_PRIO_DELTA_MAX': 25, 'SC_ARG_MAX': 0, 'SC_ASYNCHRONOUS_IO': 12, 'SC_ATEXIT_MAX': 87, 'SC_AVPHYS_PAGES': 86, 'SC_BC_BASE_MAX': 36, 'SC_BC_DIM_MAX': 37, 'SC_BC_SCALE_MAX': 38, 'SC_BC_STRING_MAX': 39, 'SC_CHARCLASS_NAME_MAX': 45, 'SC_CHAR_BIT': 101, 'SC_CHAR_MAX': 102, 'SC_CHAR_MIN': 103, 'SC_CHILD_MAX': 1, 'SC_CLK_TCK': 2, 'SC_COLL_WEIGHTS_MAX': 40, 'SC_DELAYTIMER_MAX': 26, 'SC_EQUIV_CLASS_MAX': 41, 'SC_EXPR_NEST_MAX': 42, 'SC_FSYNC': 15, 'SC_GETGR_R_SIZE_MAX': 69, 'SC_GETPW_R_SIZE_MAX': 70, 'SC_INT_MAX': 104, 'SC_INT_MIN': 105, 'SC_IOV_MAX': 60, 'SC_JOB_CONTROL': 7, 'SC_LINE_MAX': 43, 'SC_LOGIN_NAME_MAX': 71, 'SC_LONG_BIT': 106, 'SC_MAPPED_FILES': 16, 'SC_MB_LEN_MAX': 108, 'SC_MEMLOCK': 17, 'SC_MEMLOCK_RANGE': 18, 'SC_MEMORY_PROTECTION': 19, 'SC_MESSAGE_PASSING': 20, 'SC_MQ_OPEN_MAX': 27, 'SC_MQ_PRIO_MAX': 28, 'SC_NGROUPS_MAX': 3, 'SC_NL_ARGMAX': 119, 'SC_NL_LANGMAX': 120, 'SC_NL_MSGMAX': 121, 'SC_NL_NMAX': 122, 'SC_NL_SETMAX': 123, 'SC_NL_TEXTMAX': 124, 'SC_NPROCESSORS_CONF': 83, 'SC_NPROCESSORS_ONLN': 84, 'SC_NZERO': 109, 'SC_OPEN_MAX': 4, 'SC_PAGESIZE': 30, 'SC_PAGE_SIZE': 30, 'SC_PASS_MAX': 88, 'SC_PHYS_PAGES': 85, 'SC_PII': 53, 'SC_PII_INTERNET': 56, 'SC_PII_INTERNET_DGRAM': 62, 'SC_PII_INTERNET_STREAM': 61, 'SC_PII_OSI': 57, 'SC_PII_OSI_CLTS': 64, 'SC_PII_OSI_COTS': 63, 'SC_PII_OSI_M': 65, 'SC_PII_SOCKET': 55, 'SC_PII_XTI': 54, 'SC_POLL': 58, 'SC_PRIORITIZED_IO': 13, 'SC_PRIORITY_SCHEDULING': 10, 'SC_REALTIME_SIGNALS': 9, 'SC_RE_DUP_MAX': 44, 'SC_RTSIG_MAX': 31, 'SC_SAVED_IDS': 8, 'SC_SCHAR_MAX': 111, 'SC_SCHAR_MIN': 112, 'SC_SELECT': 59, 'SC_SEMAPHORES': 21, 'SC_SEM_NSEMS_MAX': 32, 'SC_SEM_VALUE_MAX': 33, 'SC_SHARED_MEMORY_OBJECTS': 22, 'SC_SHRT_MAX': 113, 'SC_SHRT_MIN': 114, 'SC_SIGQUEUE_MAX': 34, 'SC_SSIZE_MAX': 110, 'SC_STREAM_MAX': 5, 'SC_SYNCHRONIZED_IO': 14, 'SC_THREADS': 67, 'SC_THREAD_ATTR_STACKADDR': 77, 'SC_THREAD_ATTR_STACKSIZE': 78, 'SC_THREAD_DESTRUCTOR_ITERATIONS': 73, 'SC_THREAD_KEYS_MAX': 74, 'SC_THREAD_PRIORITY_SCHEDULING': 79, 'SC_THREAD_PRIO_INHERIT': 80, 'SC_THREAD_PRIO_PROTECT': 81, 'SC_THREAD_PROCESS_SHARED': 82, 'SC_THREAD_SAFE_FUNCTIONS': 68, 'SC_THREAD_STACK_MIN': 75, 'SC_THREAD_THREADS_MAX': 76, 'SC_TIMERS': 11, 'SC_TIMER_MAX': 35, 'SC_TTY_NAME_MAX': 72, 'SC_TZNAME_MAX': 6, 'SC_T_IOV_MAX': 66, 'SC_UCHAR_MAX': 115, 'SC_UINT_MAX': 116, 'SC_UIO_MAXIOV': 60, 'SC_ULONG_MAX': 117, 'SC_USHRT_MAX': 118, 'SC_VERSION': 29, 'SC_WORD_BIT': 107, 'SC_XBS5_ILP32_OFF32': 125, 'SC_XBS5_ILP32_OFFBIG': 126, 'SC_XBS5_LP64_OFF64': 127, 'SC_XBS5_LPBIG_OFFBIG': 128, 'SC_XOPEN_CRYPT': 92, 'SC_XOPEN_ENH_I18N': 93, 'SC_XOPEN_LEGACY': 129, 'SC_XOPEN_REALTIME': 130, 'SC_XOPEN_REALTIME_THREADS': 131, 'SC_XOPEN_SHM': 94, 'SC_XOPEN_UNIX': 91, 'SC_XOPEN_VERSION': 89, 'SC_XOPEN_XCU_VERSION': 90, 'SC_XOPEN_XPG2': 98, 'SC_XOPEN_XPG3': 99, 'SC_XOPEN_XPG4': 100}

Modules

abc

path

st

sys