53
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names have currently been registered: ``'posix'``, ``'nt'``,
54
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``'os2'``, ``'ce'``, ``'java'``, ``'riscos'``.
57
:attr:`sys.platform` has a finer granularity. :func:`os.uname` gives
58
system-dependent version information.
60
The :mod:`platform` module provides detailed checks for the
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On some platforms, including FreeBSD and Mac OS X, setting ``environ`` may
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cause memory leaks. Refer to the system documentation for
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If :func:`putenv` is not provided, a modified copy of this mapping may be
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passed to the appropriate process-creation functions to cause child processes
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.. function:: setpgrp()
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Call the system call :cfunc:`setpgrp` or :cfunc:`setpgrp(0, 0)` depending on
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Call the system call :c:func:`setpgrp` or :c:func:`setpgrp(0, 0)` depending on
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which version is implemented (if any). See the Unix manual for the semantics.
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Availability: Unix.
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.. function:: setpgid(pid, pgrp)
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Call the system call :cfunc:`setpgid` to set the process group id of the
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Call the system call :c:func:`setpgid` to set the process group id of the
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process with id *pid* to the process group with id *pgrp*. See the Unix manual
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for the semantics.
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.. function:: strerror(code)
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Return the error message corresponding to the error code in *code*.
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On platforms where :cfunc:`strerror` returns ``NULL`` when given an unknown
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On platforms where :c:func:`strerror` returns ``NULL`` when given an unknown
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error number, :exc:`ValueError` is raised.
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Availability: Unix, Windows.
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.. versionchanged:: 2.5
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On Unix, when the *mode* argument starts with ``'a'``, the *O_APPEND* flag is
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set on the file descriptor (which the :cfunc:`fdopen` implementation already
457
set on the file descriptor (which the :c:func:`fdopen` implementation already
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does on most platforms).
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.. versionchanged:: 2.0
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This function worked unreliably under Windows in earlier versions of Python.
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This was due to the use of the :cfunc:`_popen` function from the libraries
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This was due to the use of the :c:func:`_popen` function from the libraries
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provided with Windows. Newer versions of Python do not use the broken
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implementation from the Windows libraries.
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.. function:: fsync(fd)
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Force write of file with filedescriptor *fd* to disk. On Unix, this calls the
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native :cfunc:`fsync` function; on Windows, the MS :cfunc:`_commit` function.
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native :c:func:`fsync` function; on Windows, the MS :c:func:`_commit` function.
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If you're starting with a Python file object *f*, first do ``f.flush()``, and
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then do ``os.fsync(f.fileno())``, to ensure that all internal buffers associated
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.. function:: lstat(path)
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Perform the equivalent of an :cfunc:`lstat` system call on the given path.
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Perform the equivalent of an :c:func:`lstat` system call on the given path.
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Similar to :func:`~os.stat`, but does not follow symbolic links. On
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platforms that do not support symbolic links, this is an alias for
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:func:`~os.stat`.
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.. function:: major(device)
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Extract the device major number from a raw device number (usually the
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:attr:`st_dev` or :attr:`st_rdev` field from :ctype:`stat`).
1183
:attr:`st_dev` or :attr:`st_rdev` field from :c:type:`stat`).
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.. versionadded:: 2.3
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.. function:: minor(device)
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Extract the device minor number from a raw device number (usually the
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:attr:`st_dev` or :attr:`st_rdev` field from :ctype:`stat`).
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:attr:`st_dev` or :attr:`st_rdev` field from :c:type:`stat`).
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.. versionadded:: 2.3
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.. function:: stat(path)
1337
Perform the equivalent of a :cfunc:`stat` system call on the given path.
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Perform the equivalent of a :c:func:`stat` system call on the given path.
1338
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(This function follows symlinks; to stat a symlink use :func:`lstat`.)
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The return value is an object whose attributes correspond to the members
1341
of the :ctype:`stat` structure, namely:
1350
of the :c:type:`stat` structure, namely:
1343
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* :attr:`st_mode` - protection bits,
1344
1353
* :attr:`st_ino` - inode number,
1389
The exact meaning and resolution of the :attr:`st_atime`, :attr:`st_mtime`, and
1390
:attr:`st_ctime` members depends on the operating system and the file system.
1391
For example, on Windows systems using the FAT or FAT32 file systems,
1392
:attr:`st_mtime` has 2-second resolution, and :attr:`st_atime` has only 1-day
1393
resolution. See your operating system documentation for details.
1398
The exact meaning and resolution of the :attr:`st_atime`,
1399
:attr:`st_mtime`, and :attr:`st_ctime` attributes depend on the operating
1400
system and the file system. For example, on Windows systems using the FAT
1401
or FAT32 file systems, :attr:`st_mtime` has 2-second resolution, and
1402
:attr:`st_atime` has only 1-day resolution. See your operating system
1403
documentation for details.
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For backward compatibility, the return value of :func:`~os.stat` is also accessible
1396
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as a tuple of at least 10 integers giving the most important (and portable)
1397
members of the :ctype:`stat` structure, in the order :attr:`st_mode`,
1407
members of the :c:type:`stat` structure, in the order :attr:`st_mode`,
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:attr:`st_ino`, :attr:`st_dev`, :attr:`st_nlink`, :attr:`st_uid`,
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:attr:`st_gid`, :attr:`st_size`, :attr:`st_atime`, :attr:`st_mtime`,
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:attr:`st_ctime`. More items may be added at the end by some implementations.
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.. index:: module: stat
1404
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The standard module :mod:`stat` defines functions and constants that are useful
1405
for extracting information from a :ctype:`stat` structure. (On Windows, some
1415
for extracting information from a :c:type:`stat` structure. (On Windows, some
1406
1416
items are filled with dummy values.)
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.. function:: statvfs(path)
1454
Perform a :cfunc:`statvfs` system call on the given path. The return value is
1464
Perform a :c:func:`statvfs` system call on the given path. The return value is
1455
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an object whose attributes describe the filesystem on the given path, and
1456
correspond to the members of the :ctype:`statvfs` structure, namely:
1466
correspond to the members of the :c:type:`statvfs` structure, namely:
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:attr:`f_bsize`, :attr:`f_frsize`, :attr:`f_blocks`, :attr:`f_bfree`,
1458
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:attr:`f_bavail`, :attr:`f_files`, :attr:`f_ffree`, :attr:`f_favail`,
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:attr:`f_flag`, :attr:`f_namemax`.
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For backward compatibility, the return value is also accessible as a tuple whose
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values correspond to the attributes, in the order given above. The standard
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module :mod:`statvfs` defines constants that are useful for extracting
1466
information from a :ctype:`statvfs` structure when accessing it as a sequence;
1476
information from a :c:type:`statvfs` structure when accessing it as a sequence;
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this remains useful when writing code that needs to work with versions of Python
1468
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that don't support accessing the fields as attributes.
1588
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ineffective, because in bottom-up mode the directories in *dirnames* are
1589
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generated before *dirpath* itself is generated.
1591
By default errors from the :func:`listdir` call are ignored. If optional
1601
By default, errors from the :func:`listdir` call are ignored. If optional
1592
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argument *onerror* is specified, it should be a function; it will be called with
1593
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one argument, an :exc:`OSError` instance. It can report the error to continue
1594
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with the walk, or raise the exception to abort the walk. Note that the filename
1654
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program loaded into the process. In each case, the first of these arguments is
1655
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passed to the new program as its own name rather than as an argument a user may
1656
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have typed on a command line. For the C programmer, this is the ``argv[0]``
1657
passed to a program's :cfunc:`main`. For example, ``os.execv('/bin/echo',
1667
passed to a program's :c:func:`main`. For example, ``os.execv('/bin/echo',
1658
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['foo', 'bar'])`` will only print ``bar`` on standard output; ``foo`` will seem
1664
1674
Generate a :const:`SIGABRT` signal to the current process. On Unix, the default
1665
1675
behavior is to produce a core dump; on Windows, the process immediately returns
1666
an exit code of ``3``. Be aware that programs which use :func:`signal.signal`
1667
to register a handler for :const:`SIGABRT` will behave differently.
1676
an exit code of ``3``. Be aware that calling this function will not call the
1677
Python signal handler registered for :const:`SIGABRT` with
1678
:func:`signal.signal`.
1669
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Availability: Unix, Windows.
2041
2052
os.spawnvpe(os.P_WAIT, 'cp', L, os.environ)
2043
2054
Availability: Unix, Windows. :func:`spawnlp`, :func:`spawnlpe`, :func:`spawnvp`
2044
and :func:`spawnvpe` are not available on Windows.
2055
and :func:`spawnvpe` are not available on Windows. :func:`spawnle` and
2056
:func:`spawnve` are not thread-safe on Windows; we advise you to use the
2057
:mod:`subprocess` module instead.
2046
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.. versionadded:: 1.6
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There is no option to wait for the application to close, and no way to retrieve
2105
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the application's exit status. The *path* parameter is relative to the current
2106
2119
directory. If you want to use an absolute path, make sure the first character
2107
is not a slash (``'/'``); the underlying Win32 :cfunc:`ShellExecute` function
2120
is not a slash (``'/'``); the underlying Win32 :c:func:`ShellExecute` function
2108
2121
doesn't work if it is. Use the :func:`os.path.normpath` function to ensure that
2109
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the path is properly encoded for Win32.
2119
2132
.. function:: system(command)
2121
2134
Execute the command (a string) in a subshell. This is implemented by calling
2122
the Standard C function :cfunc:`system`, and has the same limitations.
2135
the Standard C function :c:func:`system`, and has the same limitations.
2123
2136
Changes to :data:`sys.stdin`, etc. are not reflected in the environment of the
2124
2137
executed command.
2126
2139
On Unix, the return value is the exit status of the process encoded in the
2127
2140
format specified for :func:`wait`. Note that POSIX does not specify the meaning
2128
of the return value of the C :cfunc:`system` function, so the return value of
2141
of the return value of the C :c:func:`system` function, so the return value of
2129
2142
the Python function is system-dependent.
2131
2144
On Windows, the return value is that returned by the system shell after running
added
removed
Doc/library/os.rst
