traverseda
/
cpython
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Merged upstream changes.

This commit is contained in:
Vinay Sajip 2012-06-24 11:24:05 +01:00
parent d89dae18e8 78f075636c
commit dd7987382d
6 changed files with 284 additions and 364 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
Doc/library/email.headerregistry.rst
View File

@ -268,7 +268,7 @@ variant, :attr:`~.BaseHeader.max_count` is set to 1.
also take a list of supplemental parameters, which have a common format.
This class serves as a base for all the MIME headers that take parameters.
.. attrbibute:: params
.. attribute:: params
A dictionary mapping parameter names to parameter values.

548
Doc/library/os.rst
View File

@ -645,7 +645,7 @@ as internal buffering of data.
.. function:: closerange(fd_low, fd_high)
Close all file descriptors from *fd_low* (inclusive) to *fd_high* (exclusive),
ignoring errors. Equivalent to::
ignoring errors. Equivalent to (but much faster than)::
for fd in range(fd_low, fd_high):
try:
@ -729,6 +729,7 @@ as internal buffering of data.
Availability: Unix, Windows.
.. function:: fstatvfs(fd)
Return information about the filesystem containing the file associated with file
@ -823,13 +824,8 @@ as internal buffering of data.
this module too (see :ref:`open-constants`). In particular, on Windows adding
:const:`O_BINARY` is needed to open files in binary mode.
If *dir_fd* is not ``None``, it should be a file descriptor referring to a
directory, and *path* should be relative; path will then be relative to
that directory. (If *path* is absolute, *dir_fd* is ignored.)
*dir_fd* may not be supported on your platform;
you can check whether or not it is available using
:data:`os.supports_dir_fd`. If it is unavailable, using it will raise
a :exc:`NotImplementedError`.
This function can support :ref:`paths relative to directory descriptors
<dir_fd>`.
Availability: Unix, Windows.
@ -1171,6 +1167,49 @@ Querying the size of a terminal
Files and Directories
---------------------
On some Unix platforms, many of these functions support one or more of these
features:
.. _path_fd:
* For some functions, the *path* argument can be not only a string giving a path
name, but also a file descriptor. The function will then operate on the file
referred to by the descriptor. (For POSIX systems, this will use the ``f...``
versions of the function.)
You can check whether or not *path* can be specified as a file descriptor on
your platform using :data:`os.supports_fd`. If it is unavailable, using it
will raise a :exc:`NotImplementedError`.
If the function also supports *dir_fd* or *follow_symlinks* arguments, it is
an error to specify one of those when supplying *path* as a file descriptor.
.. _dir_fd:
* For functions with a *dir_fd* parameter: If *dir_fd* is not ``None``, it
should be a file descriptor referring to a directory, and the path to operate
on should be relative; path will then be relative to that directory. If the
path is absolute, *dir_fd* is ignored. (For POSIX systems, this will use the
``f...at`` versions of the function.)
You can check whether or not *dir_fd* is supported on your platform using
:data:`os.supports_dir_fd`. If it is unavailable, using it will raise a
:exc:`NotImplementedError`.
.. _follow_symlinks:
* For functions ith a *follow_symlinks* parameter: If *follow_symlinks* is
``False``, and the last element of the path to operate on is a symbolic link,
the function will operate on the symbolic link itself instead of the file the
link points to. (For POSIX systems, this will use the ``l...`` versions of
the function.)
You can check whether or not *follow_symlinks* is supported on your platform
using :data:`os.supports_follow_symlinks`. If it is unavailable, using it
will raise a :exc:`NotImplementedError`.
.. function:: access(path, mode, *, dir_fd=None, effective_ids=False, follow_symlinks=True)
Use the real uid/gid to test for access to *path*. Note that most operations
@ -1182,13 +1221,8 @@ Files and Directories
:const:`False` if not. See the Unix man page :manpage:`access(2)` for more
information.
If *dir_fd* is not ``None``, it should be a file descriptor referring to a
directory, and *path* should be relative; path will then be relative to
that directory. (If *path* is absolute, *dir_fd* is ignored.)
*dir_fd* may not be supported on your platform;
you can check whether or not it is available using
:data:`os.supports_dir_fd`. If it is unavailable, using it will raise
a :exc:`NotImplementedError`.
This function can support specifying :ref:`paths relative to directory
descriptors <dir_fd>` and :ref:`not following symlinks <follow_symlinks>`.
If *effective_ids* is ``True``, :func:`access` will perform its access
checks using the effective uid/gid instead of the real uid/gid.
@ -1196,13 +1230,6 @@ Files and Directories
or not it is available using :data:`os.supports_effective_ids`. If it is
unavailable, using it will raise a :exc:`NotImplementedError`.
If *follow_symlinks* is ``False``, and the last element of the path is a
symbolic link, :func:`access` will examine the symbolic link itself instead
of the file the link points to. *follow_symlinks* may not be supported
on your platform; you can check whether or not it is available using
:data:`os.supports_follow_symlinks`. If it is unavailable,
using it will raise a :exc:`NotImplementedError`.
Availability: Unix, Windows.
.. note::
@ -1268,24 +1295,21 @@ Files and Directories
Change the current working directory to *path*.
On some platforms, *path* may also be specified as an open file descriptor.
This functionality may not be supported on your platform; you can check
whether or not it is available using :data:`os.supports_fd`. If it is
unavailable, using it will raise a :exc:`NotImplementedError`.
This function can support :ref:`working on a file descriptor <path_fd>`. The
descriptor must refer to an opened directory, not an open file.
Availability: Unix, Windows.
.. versionadded:: 3.3
Added support for specifying *path* as a file descriptor
on some platforms, and the *dir_fd*, *effective_ids*, and
*follow_symlinks* parameters.
on some platforms.
.. function:: fchdir(fd)
Change the current working directory to the directory represented by the file
descriptor *fd*. The descriptor must refer to an opened directory, not an open
file. Equivalent to ``os.chdir(fd)``.
descriptor *fd*. The descriptor must refer to an opened directory, not an
open file. Equivalent to ``os.chdir(fd)``.
Availability: Unix.
@ -1322,12 +1346,7 @@ Files and Directories
* :data:`stat.SF_NOUNLINK`
* :data:`stat.SF_SNAPSHOT`
If *follow_symlinks* is ``False``, and the last element of the path is a
symbolic link, :func:`follow_symlinks` will examine the symbolic link itself
instead of the file the link points to. *follow_symlinks* may not be
supported on your platform; you can check whether or not it is available
using :data:`os.supports_follow_symlinks`. If it is unavailable,
using it will raise a :exc:`NotImplementedError`.
This function can support :ref:`not following symlinks <follow_symlinks>`.
Availability: Unix.
@ -1367,37 +1386,17 @@ Files and Directories
* :data:`stat.S_IWOTH`
* :data:`stat.S_IXOTH`
On some platforms, *path* may also be specified as an open file descriptor.
This functionality may not be supported on your platform; you can check
whether or not it is available using :data:`os.supports_fd`. If it is
unavailable, using it will raise a :exc:`NotImplementedError`.
If *dir_fd* is not ``None``, it should be a file descriptor referring to a
directory, and *path* should be relative; path will then be relative to
that directory. (If *path* is absolute, *dir_fd* is ignored.)
*dir_fd* may not be supported on your platform;
you can check whether or not it is available using
:data:`os.supports_dir_fd`. If it is unavailable, using it will raise
a :exc:`NotImplementedError`.
If *follow_symlinks* is ``False``, and the last element of the path is a
symbolic link, :func:`chmod` will examine the symbolic link itself instead
of the file the link points to. *follow_symlinks* may not be supported
on your platform; you can check whether or not it is available using
:data:`os.supports_follow_symlinks`. If it is unavailable,
using it will raise a :exc:`NotImplementedError`.
It is an error to use *dir_fd* or *follow_symlinks* when specifying
*path* as an open file descriptor.
This function can support :ref:`specifying a file descriptor <path_fd>`,
:ref:`paths relative to directory descriptors <dir_fd>` and :ref:`not
following symlinks <follow_symlinks>`.
Availability: Unix, Windows.
.. note::
Although Windows supports :func:`chmod`, you can only set the file's read-only
flag with it (via the ``stat.S_IWRITE`` and ``stat.S_IREAD``
constants or a corresponding integer value). All other bits are
ignored.
Although Windows supports :func:`chmod`, you can only set the file's
read-only flag with it (via the ``stat.S_IWRITE`` and ``stat.S_IREAD``
constants or a corresponding integer value). All other bits are ignored.
.. versionadded:: 3.3
Added support for specifying *path* as an open file descriptor,
@ -1406,31 +1405,12 @@ Files and Directories
.. function:: chown(path, uid, gid, *, dir_fd=None, follow_symlinks=True)
Change the owner and group id of *path* to the numeric *uid* and *gid*. To leave
one of the ids unchanged, set it to -1.
Change the owner and group id of *path* to the numeric *uid* and *gid*. To
leave one of the ids unchanged, set it to -1.
On some platforms, *path* may also be specified as an open file descriptor.
This functionality may not be supported on your platform; you can check
whether or not it is available using :data:`os.supports_fd`. If it is
unavailable, using it will raise a :exc:`NotImplementedError`.
If *dir_fd* is not ``None``, it should be a file descriptor referring to a
directory, and *path* should be relative; path will then be relative to
that directory. (If *path* is absolute, *dir_fd* is ignored.)
*dir_fd* may not be supported on your platform;
you can check whether or not it is available using
:data:`os.supports_dir_fd`. If it is unavailable, using it will raise
a :exc:`NotImplementedError`.
If *follow_symlinks* is ``False``, and the last element of the path is a
symbolic link, :func:`chown` will examine the symbolic link itself instead
of the file the link points to. *follow_symlinks* may not be supported
on your platform; you can check whether or not it is available using
:data:`os.supports_follow_symlinks`. If it is unavailable,
using it will raise a :exc:`NotImplementedError`.
It is an error to use *dir_fd* or *follow_symlinks* when specifying
*path* as an open file descriptor.
This function can support :ref:`specifying a file descriptor <path_fd>`,
:ref:`paths relative to directory descriptors <dir_fd>` and :ref:`not
following symlinks <follow_symlinks>`.
See :func:`shutil.chown` for a higher-level function that accepts names in
addition to numeric ids.
@ -1442,29 +1422,11 @@ Files and Directories
and the *dir_fd* and *follow_symlinks* arguments.
.. function:: getxattr(path, attribute, *, follow_symlinks=True)
Return the value of the extended filesystem attribute *attribute* for
*path*. *attribute* can be bytes or str. If it is str, it is encoded
with the filesystem encoding.
*path* may be specified as either a string or an open file descriptor.
If *follow_symlinks* is ``False``, and the last element of the path is a
symbolic link, :func:`setxattr` will examine the symbolic link itself
instead of the file the link points to. It is an error to use
*follow_symlinks* when specifying *path* as an open file descriptor.
Availability: Linux
.. versionadded:: 3.3
.. function:: lchflags(path, flags)
Set the flags of *path* to the numeric *flags*, like :func:`chflags`, but do not
follow symbolic links.
Equivalent to ``os.chflags(path, flags, follow_symlinks=False)``.
Set the flags of *path* to the numeric *flags*, like :func:`chflags`, but do
not follow symbolic links. Equivalent to ``os.chflags(path, flags,
follow_symlinks=False)``.
Availability: Unix.
@ -1472,18 +1434,18 @@ Files and Directories
.. function:: lchmod(path, mode)
Change the mode of *path* to the numeric *mode*. If path is a symlink, this
affects the symlink rather than the target. See the docs for :func:`chmod`
for possible values of *mode*.
Equivalent to ``os.chmod(path, mode, follow_symlinks=False)``.
affects the symlink rather than the target. See the docs for :func:`chmod`
for possible values of *mode*. Equivalent to ``os.chmod(path, mode,
follow_symlinks=False)``.
Availability: Unix.
.. function:: 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)``.
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)``.
Availability: Unix.
@ -1492,21 +1454,17 @@ Files and Directories
Create a hard link pointing to *src* named *dst*.
If either *src_dir_fd* or *dst_dir_fd* is not ``None``, it should be a
file descriptor referring to a directory, and the corresponding path
(*src* or *dst*) should be relative; that path will then be relative to
that directory. (If *src* is absolute, *src_dir_fd* is ignored; the same
goes for *dst* and *dst_dir_fd*.)
*src_dir_fd* and *dst_dir_fd* may not be supported on your platform;
you can check whether or not they are available using :data:`os.supports_dir_fd`.
If they are unavailable, using either will raise a :exc:`NotImplementedError`.
If either *src_dir_fd* or *dst_dir_fd* is not ``None``, it should be a file
descriptor referring to a directory, and the corresponding path (*src* or
*dst*) should be relative; that path will then be relative to that directory.
(If *src* is absolute, *src_dir_fd* is ignored; the same goes for *dst* and
*dst_dir_fd*.) *src_dir_fd* and *dst_dir_fd* may not be supported on your
platform; you can check whether or not they are available using
:data:`os.supports_dir_fd`. If they are unavailable, using either will raise
a :exc:`NotImplementedError`.
If *follow_symlinks* is ``False``, and the last element of *src* is a
symbolic link, :func:`link` will use the symbolic link itself instead
of the file the link points to. *follow_symlinks* may not be supported
on your platform; you can check whether or not it is available using
:data:`os.supports_follow_symlinks`. If it is unavailable,
using it will raise a :exc:`NotImplementedError`.
This function can also support :ref:`not following symlinks
<follow_symlinks>`.
Availability: Unix, Windows.
@ -1520,16 +1478,15 @@ Files and Directories
.. function:: listdir(path='.')
Return a list containing the names of the entries in the directory given by
*path* (default: ``'.'``). The list is in arbitrary order. It does not include the special
entries ``'.'`` and ``'..'`` even if they are present in the directory.
*path* (default: ``'.'``). The list is in arbitrary order. It does not
include the special entries ``'.'`` and ``'..'`` even if they are present in
the directory.
This function can be called with a bytes or string argument, and returns
filenames of the same datatype.
On some platforms, *path* may also be specified as an open file descriptor.
This functionality may not be supported on your platform; you can check
whether or not it is available using :data:`os.supports_fd`. If it is
unavailable, using it will raise a :exc:`NotImplementedError`.
This function can also support :ref:`specifying an open file descriptor
<path_fd>` (referring to a directory).
Availability: Unix, Windows.
@ -1539,25 +1496,6 @@ Files and Directories
.. versionadded:: 3.3
Added support for specifying an open file descriptor for *path*.
.. function:: listxattr(path=None, *, follow_symlinks=True)
Return a list of the extended filesystem attributes on *path*.
The attributes in the list are represented as strings decoded
with the filesystem encoding.
*path* may be specified as either ``None``, a string, or an open file
descriptor. If *path* is ``None``, :func:`listxattr` will examine the
current directory.
If *follow_symlinks* is ``False``, and the last element of the path is a
symbolic link, :func:`listxattr` will examine the symbolic link itself
instead of the file the link points to. It is an error to use
*follow_symlinks* when specifying *path* as an open file descriptor.
Availability: Linux
.. versionadded:: 3.3
.. function:: lstat(path, *, dir_fd=None)
@ -1566,13 +1504,8 @@ Files and Directories
platforms that do not support symbolic links, this is an alias for
:func:`~os.stat`. (Equivalent to ``os.stat(path, follow_symlinks=False)``.)
If *dir_fd* is not ``None``, it should be a file descriptor referring to a
directory, and *path* should be relative; path will then be relative to
that directory. (If *path* is absolute, *dir_fd* is ignored.)
*dir_fd* may not be supported on your platform;
you can check whether or not it is available using
:data:`os.supports_dir_fd`. If it is unavailable, using it will raise
a :exc:`NotImplementedError`.
This function can also support :ref:`paths relative to directory descriptors
<dir_fd>`.
.. versionchanged:: 3.2
Added support for Windows 6.0 (Vista) symbolic links.
@ -1586,13 +1519,8 @@ Files and Directories
Create a FIFO (a named pipe) named *path* with numeric mode *mode*.
The current umask value is first masked out from the mode.
If *dir_fd* is not ``None``, it should be a file descriptor referring to a
directory, and *path* should be relative; path will then be relative to
that directory. (If *path* is absolute, *dir_fd* is ignored.)
*dir_fd* may not be supported on your platform;
you can check whether or not it is available using
:data:`os.supports_dir_fd`. If it is unavailable, using it will raise
a :exc:`NotImplementedError`.
This function can also support :ref:`paths relative to directory descriptors
<dir_fd>`.
FIFOs are pipes that can be accessed like regular files. FIFOs exist until they
are deleted (for example with :func:`os.unlink`). Generally, FIFOs are used as
@ -1616,13 +1544,8 @@ Files and Directories
*device* defines the newly created device special file (probably using
:func:`os.makedev`), otherwise it is ignored.
If *dir_fd* is not ``None``, it should be a file descriptor referring to a
directory, and *path* should be relative; path will then be relative to
that directory. (If *path* is absolute, *dir_fd* is ignored.)
*dir_fd* may not be supported on your platform;
you can check whether or not it is available using
:data:`os.supports_dir_fd`. If it is unavailable, using it will raise
a :exc:`NotImplementedError`.
This function can also support :ref:`paths relative to directory descriptors
<dir_fd>`.
.. versionadded:: 3.3
The *dir_fd* argument.
@ -1649,17 +1572,12 @@ Files and Directories
Create a directory named *path* with numeric mode *mode*.
On some systems, *mode* is ignored. Where it is used, the current
umask value is first masked out. If the directory already
exists, :exc:`OSError` is raised.
On some systems, *mode* is ignored. Where it is used, the current umask
value is first masked out. If the directory already exists, :exc:`OSError`
is raised.
If *dir_fd* is not ``None``, it should be a file descriptor referring to a
directory, and *path* should be relative; path will then be relative to
that directory. (If *path* is absolute, *dir_fd* is ignored.)
*dir_fd* may not be supported on your platform;
you can check whether or not it is available using
:data:`os.supports_dir_fd`. If it is unavailable, using it will raise
a :exc:`NotImplementedError`.
This function can also support :ref:`paths relative to directory descriptors
<dir_fd>`.
It is also possible to create temporary directories; see the
:mod:`tempfile` module's :func:`tempfile.mkdtemp` function.
@ -1725,21 +1643,16 @@ Files and Directories
.. function:: readlink(path, *, dir_fd=None)
Return a string representing the path to which the symbolic link points. The
result may be either an absolute or relative pathname; if it is relative, it may
be converted to an absolute pathname using ``os.path.join(os.path.dirname(path),
result)``.
result may be either an absolute or relative pathname; if it is relative, it
may be converted to an absolute pathname using
``os.path.join(os.path.dirname(path), result)``.
If the *path* is a string object, the result will also be a string object,
and the call may raise an UnicodeDecodeError. If the *path* is a bytes
object, the result will be a bytes object.
If *dir_fd* is not ``None``, it should be a file descriptor referring to a
directory, and *path* should be relative; path will then be relative to
that directory. (If *path* is absolute, *dir_fd* is ignored.)
*dir_fd* may not be supported on your platform;
you can check whether or not it is available using
:data:`os.supports_dir_fd`. If it is unavailable, using it will raise
a :exc:`NotImplementedError`.
This function can also support :ref:`paths relative to directory descriptors
<dir_fd>`.
Availability: Unix, Windows
@ -1752,16 +1665,11 @@ Files and Directories
.. function:: remove(path, *, dir_fd=None)
Remove (delete) the file *path*. If *path* is a directory, :exc:`OSError`
is raised. Use :func:`rmdir` to remove directories.
Remove (delete) the file *path*. If *path* is a directory, :exc:`OSError` is
raised. Use :func:`rmdir` to remove directories.
If *dir_fd* is not ``None``, it should be a file descriptor referring to a
directory, and *path* should be relative; path will then be relative to
that directory. (If *path* is absolute, *dir_fd* is ignored.)
*dir_fd* may not be supported on your platform;
you can check whether or not it is available using
:data:`os.supports_dir_fd`. If it is unavailable, using it will raise
a :exc:`NotImplementedError`.
This function can support :ref:`paths relative to directory descriptors
<dir_fd>`.
On Windows, attempting to remove a file that is in use causes an exception to
be raised; on Unix, the directory entry is removed but the storage allocated
@ -1789,25 +1697,6 @@ Files and Directories
successfully removed.
.. function:: removexattr(path, attribute, *, follow_symlinks=True)
Removes the extended filesystem attribute *attribute* from *path*.
*attribute* should be bytes or str. If it is a string, it is encoded
with the filesystem encoding.
*path* may be specified as either a string or an open file descriptor.
If *follow_symlinks* is ``False``, and the last element of the path is a
symbolic link, :func:`removexattr` will remove the attribute from the
symbolic link itself instead of the file the link points to. It is an
error to use *follow_symlinks* when specifying *path* as an open file
descriptor.
Availability: Linux
.. versionadded:: 3.3
.. function:: rename(src, dst, *, src_dir_fd=None, dst_dir_fd=None)
Rename the file or directory *src* to *dst*. If *dst* is a directory,
@ -1876,13 +1765,8 @@ Files and Directories
empty, otherwise, :exc:`OSError` is raised. In order to remove whole
directory trees, :func:`shutil.rmtree` can be used.
If *dir_fd* is not ``None``, it should be a file descriptor referring to a
directory, and *path* should be relative; path will then be relative to
that directory. (If *path* is absolute, *dir_fd* is ignored.)
*dir_fd* may not be supported on your platform;
you can check whether or not it is available using
:data:`os.supports_dir_fd`. If it is unavailable, using it will raise
a :exc:`NotImplementedError`.
This function can support :ref:`paths relative to directory descriptors
<dir_fd>`.
Availability: Unix, Windows.
@ -1890,51 +1774,6 @@ Files and Directories
The *dir_fd* parameter.
.. data:: XATTR_SIZE_MAX
The maximum size the value of an extended attribute can be. Currently, this
is 64 kilobytes on Linux.
.. data:: XATTR_CREATE
This is a possible value for the flags argument in :func:`setxattr`. It
indicates the operation must create an attribute.
.. data:: XATTR_REPLACE
This is a possible value for the flags argument in :func:`setxattr`. It
indicates the operation must replace an existing attribute.
.. function:: setxattr(path, attribute, value, flags=0, *, follow_symlinks=True)
Set the extended filesystem attribute *attribute* on *path* to *value*.
*attribute* must be a bytes or str with no embedded NULs. If it is a str,
it is encoded with the filesystem encoding. *flags* may be
:data:`XATTR_REPLACE` or :data:`XATTR_CREATE`. If :data:`XATTR_REPLACE` is
given and the attribute does not exist, ``EEXISTS`` will be raised.
If :data:`XATTR_CREATE` is given and the attribute already exists, the
attribute will not be created and ``ENODATA`` will be raised.
*path* may be specified as either a string or an open file descriptor.
If *follow_symlinks* is ``False``, and the last element of the path is a
symbolic link, :func:`setxattr` will examine the symbolic link itself
instead of the file the link points to. It is an error to use
*follow_symlinks* when specifying *path* as an open file descriptor.
Availability: Linux
.. note::
A bug in Linux kernel versions less than 2.6.39 caused the flags argument
to be ignored on some filesystems.
.. versionadded:: 3.3
.. function:: stat(path, *, dir_fd=None, follow_symlinks=True)
Perform the equivalent of a :c:func:`stat` system call on the given path.
@ -2002,30 +1841,17 @@ Files and Directories
If you need the exact timestamps you should always use
:attr:`st_atime_ns`, :attr:`st_mtime_ns`, and :attr:`st_ctime_ns`.
For backward compatibility, the return value of :func:`~os.stat` is also accessible
as a tuple of at least 10 integers giving the most important (and portable)
members of the :c:type:`stat` structure, in the order :attr:`st_mode`,
:attr:`st_ino`, :attr:`st_dev`, :attr:`st_nlink`, :attr:`st_uid`,
:attr:`st_gid`, :attr:`st_size`, :attr:`st_atime`, :attr:`st_mtime`,
:attr:`st_ctime`. More items may be added at the end by some implementations.
For backward compatibility, the return value of :func:`~os.stat` is also
accessible as a tuple of at least 10 integers giving the most important (and
portable) members of the :c:type:`stat` structure, in the order
:attr:`st_mode`, :attr:`st_ino`, :attr:`st_dev`, :attr:`st_nlink`,
:attr:`st_uid`, :attr:`st_gid`, :attr:`st_size`, :attr:`st_atime`,
:attr:`st_mtime`, :attr:`st_ctime`. More items may be added at the end by
some implementations.
If *dir_fd* is not ``None``, it should be a file descriptor referring to a
directory, and *path* should be relative; path will then be relative to
that directory. (If *path* is absolute, *dir_fd* is ignored.)
*dir_fd* may not be supported on your platform;
you can check whether or not it is available using
:data:`os.supports_dir_fd`. If it is unavailable, using it will raise
a :exc:`NotImplementedError`.
If *follow_symlinks* is ``False``, and the last element of the path is a
symbolic link, :func:`stat` will examine the symbolic link itself instead
of the file the link points to. *follow_symlinks* may not be supported
on your platform; you can check whether or not it is available using
:data:`os.supports_follow_symlinks`. If it is unavailable,
using it will raise a :exc:`NotImplementedError`.
It is an error to use *dir_fd* or *follow_symlinks* when specifying
*path* as an open file descriptor.
This function can support :ref:`specifying an open file descriptor
<path_fd>`, :ref:`specifying a file descriptor <path_fd>` and :ref:`not
following symlinks <follow_symlinks>`.
.. index:: module: stat
@ -2094,10 +1920,7 @@ Files and Directories
read-only, and if :const:`ST_NOSUID` is set, the semantics of
setuid/setgid bits are disabled or not supported.
On some platforms, *path* may also be specified as an open file descriptor.
This functionality may not be supported on your platform; you can check
whether or not it is available using :data:`os.supports_fd`. If it is
unavailable, using it will raise a :exc:`NotImplementedError`.
This function can support :ref:`specifying a file descriptor <path_fd>`.
.. versionchanged:: 3.2
The :const:`ST_RDONLY` and :const:`ST_NOSUID` constants were added.
@ -2132,17 +1955,17 @@ Files and Directories
.. data:: supports_effective_ids
An object implementing collections.Set indicating which functions in the
:mod:`os` permit use of the *effective_id* parameter for :func:`os.access`.
:mod:`os` permit use of the *effective_ids* parameter for :func:`os.access`.
If the local platform supports it, the collection will contain
:func:`os.access`, otherwise it will be empty.
To check whether you can use the *effective_id* parameter for
To check whether you can use the *effective_ids* parameter for
:func:`os.access`, use the ``in`` operator on ``supports_dir_fd``, like so::
os.access in os.supports_effective_ids
Currently *effective_id* only works on UNIX platforms;
it does not work on Windows.
Currently *effective_ids* only works on Unix platforms; it does not work on
Windows.
.. versionadded:: 3.3
@ -2196,13 +2019,8 @@ Files and Directories
Symbolic link support was introduced in Windows 6.0 (Vista). :func:`symlink`
will raise a :exc:`NotImplementedError` on Windows versions earlier than 6.0.
If *dir_fd* is not ``None``, it should be a file descriptor referring to a
directory, and *path* should be relative; path will then be relative to
that directory. (If *path* is absolute, *dir_fd* is ignored.)
*dir_fd* may not be supported on your platform;
you can check whether or not it is available using
:data:`os.supports_dir_fd`. If it is unavailable, using it will raise
a :exc:`NotImplementedError`.
This function can support :ref:`paths relative to directory descriptors
<dir_fd>`.
.. note::
@ -2247,7 +2065,7 @@ Files and Directories
.. function:: unlink(path, *, dir_fd=None)
Remove (delete) the file *path*. This function is identical to
:func:`remove`; the :func:`unlink` name is its traditional Unix
:func:`remove`; the ``unlink`` name is its traditional Unix
name. Please see the documentation for :func:`remove` for
further information.
@ -2287,28 +2105,9 @@ Files and Directories
use the *st_atime_ns* and *st_mtime_ns* fields from the :func:`os.stat`
result object with the *ns* parameter to `utime`.
On some platforms, *path* may also be specified as an open file descriptor.
This functionality may not be supported on your platform; you can check
whether or not it is available using :data:`os.supports_fd`. If it is
unavailable, using it will raise a :exc:`NotImplementedError`.
If *dir_fd* is not ``None``, it should be a file descriptor referring to a
directory, and *path* should be relative; path will then be relative to
that directory. (If *path* is absolute, *dir_fd* is ignored.)
*dir_fd* may not be supported on your platform;
you can check whether or not it is available using
:data:`os.supports_dir_fd`. If it is unavailable, using it will raise
a :exc:`NotImplementedError`.
If *follow_symlinks* is ``False``, and the last element of the path is a
symbolic link, :func:`utime` will examine the symbolic link itself instead
of the file the link points to. *follow_symlinks* may not be supported
on your platform; you can check whether or not it is available using
:data:`os.supports_follow_symlinks`. If it is unavailable,
using it will raise a :exc:`NotImplementedError`.
It is an error to use *dir_fd* or *follow_symlinks* when specifying
*path* as an open file descriptor.
This function can support :ref:`specifying a file descriptor <path_fd>`,
:ref:`paths relative to directory descriptors <dir_fd>` and :ref:`not
following symlinks <follow_symlinks>`.
Availability: Unix, Windows.
@ -2362,9 +2161,9 @@ Files and Directories
.. note::
Be aware that setting *followlinks* to ``True`` can lead to infinite recursion if a
link points to a parent directory of itself. :func:`walk` does not keep track of
the directories it visited already.
Be aware that setting *followlinks* to ``True`` can lead to infinite
recursion if a link points to a parent directory of itself. :func:`walk`
does not keep track of the directories it visited already.
.. note::
@ -2451,6 +2250,81 @@ Files and Directories
.. versionadded:: 3.3
Linux extended attributes
~~~~~~~~~~~~~~~~~~~~~~~~~
.. versionadded:: 3.3
These functions are all available on Linux only.
.. function:: getxattr(path, attribute, *, follow_symlinks=True)
Return the value of the extended filesystem attribute *attribute* for
*path*. *attribute* can be bytes or str. If it is str, it is encoded
with the filesystem encoding.
This function can support :ref:`specifying a file descriptor <path_fd>` and
:ref:`not following symlinks <follow_symlinks>`.
.. function:: listxattr(path=None, *, follow_symlinks=True)
Return a list of the extended filesystem attributes on *path*. The
attributes in the list are represented as strings decoded with the filesystem
encoding. If *path* is ``None``, :func:`listxattr` will examine the current
directory.
This function can support :ref:`specifying a file descriptor <path_fd>` and
:ref:`not following symlinks <follow_symlinks>`.
.. function:: removexattr(path, attribute, *, follow_symlinks=True)
Removes the extended filesystem attribute *attribute* from *path*.
*attribute* should be bytes or str. If it is a string, it is encoded
with the filesystem encoding.
This function can support :ref:`specifying a file descriptor <path_fd>` and
:ref:`not following symlinks <follow_symlinks>`.
.. function:: setxattr(path, attribute, value, flags=0, *, follow_symlinks=True)
Set the extended filesystem attribute *attribute* on *path* to *value*.
*attribute* must be a bytes or str with no embedded NULs. If it is a str,
it is encoded with the filesystem encoding. *flags* may be
:data:`XATTR_REPLACE` or :data:`XATTR_CREATE`. If :data:`XATTR_REPLACE` is
given and the attribute does not exist, ``EEXISTS`` will be raised.
If :data:`XATTR_CREATE` is given and the attribute already exists, the
attribute will not be created and ``ENODATA`` will be raised.
This function can support :ref:`specifying a file descriptor <path_fd>` and
:ref:`not following symlinks <follow_symlinks>`.
.. note::
A bug in Linux kernel versions less than 2.6.39 caused the flags argument
to be ignored on some filesystems.
.. data:: XATTR_SIZE_MAX
The maximum size the value of an extended attribute can be. Currently, this
is 64 kilobytes on Linux.
.. data:: XATTR_CREATE
This is a possible value for the flags argument in :func:`setxattr`. It
indicates the operation must create an attribute.
.. data:: XATTR_REPLACE
This is a possible value for the flags argument in :func:`setxattr`. It
indicates the operation must replace an existing attribute.
.. _os-process:
Process Management

6
Lib/test/test_random.py
View File

@ -34,8 +34,12 @@ class TestBasicOps(unittest.TestCase):
self.assertEqual(randseq, self.randomlist(N))
def test_seedargs(self):
# Seed value with a negative hash.
class MySeed(object):
def __hash__(self):
return -1729
for arg in [None, 0, 0, 1, 1, -1, -1, 10**20, -(10**20),
3.14, 1+2j, 'a', tuple('abc')]:
3.14, 1+2j, 'a', tuple('abc'), MySeed()]:
self.gen.seed(arg)
for arg in [list(range(3)), dict(one=1)]:
self.assertRaises(TypeError, self.gen.seed, arg)

4
Misc/NEWS
View File

@ -55,6 +55,10 @@ Core and Builtins
Library
-------
- Speed up _decimal by another 10-15% by caching the thread local context
that was last accessed. In the pi benchmark (64-bit platform, prec=9),
_decimal is now only 1.5x slower than float.
- Remove the packaging module, which is not ready for prime time.
- Issue #15154: Add "dir_fd" parameter to os.rmdir, remove "rmdir"

79
Modules/_decimal/_decimal.c
View File

@ -76,6 +76,9 @@ typedef struct {
PyObject *traps;
PyObject *flags;
int capitals;
#ifndef WITHOUT_THREADS
PyThreadState *tstate;
#endif
} PyDecContextObject;
typedef struct {
@ -123,6 +126,8 @@ static PyObject *module_context = NULL;
#else
/* Key for thread state dictionary */
static PyObject *tls_context_key = NULL;
/* Invariant: NULL or the most recently accessed thread local context */
static PyDecContextObject *cached_context = NULL;
#endif
/* Template for creating new thread contexts, calling Context() without
@ -1182,6 +1187,9 @@ context_new(PyTypeObject *type, PyObject *args UNUSED, PyObject *kwds UNUSED)
SdFlagAddr(self->flags) = &ctx->status;
CtxCaps(self) = 1;
#ifndef WITHOUT_THREADS
self->tstate = NULL;
#endif
return (PyObject *)self;
}
@ -1189,6 +1197,11 @@ context_new(PyTypeObject *type, PyObject *args UNUSED, PyObject *kwds UNUSED)
static void
context_dealloc(PyDecContextObject *self)
{
#ifndef WITHOUT_THREADS
if (self == cached_context) {
cached_context = NULL;
}
#endif
Py_XDECREF(self->traps);
Py_XDECREF(self->flags);
Py_TYPE(self)->tp_free(self);
@ -1555,18 +1568,19 @@ PyDec_SetCurrentContext(PyObject *self UNUSED, PyObject *v)
}
#else
/*
* Thread local storage currently has a speed penalty of about 16%.
* Thread local storage currently has a speed penalty of about 4%.
* All functions that map Python's arithmetic operators to mpdecimal
* functions have to look up the current context for each and every
* operation.
*/
/* Return borrowed reference to thread local context. */
/* Get the context from the thread state dictionary. */
static PyObject *
current_context(void)
current_context_from_dict(void)
{
PyObject *dict = NULL;
PyObject *tl_context = NULL;
PyObject *dict;
PyObject *tl_context;
PyThreadState *tstate;
dict = PyThreadState_GetDict();
if (dict == NULL) {
@ -1577,32 +1591,54 @@ current_context(void)
tl_context = PyDict_GetItemWithError(dict, tls_context_key);
if (tl_context != NULL) {
/* We already have a thread local context and
* return a borrowed reference. */
/* We already have a thread local context. */
CONTEXT_CHECK(tl_context);
return tl_context;
}
if (PyErr_Occurred()) {
return NULL;
}
else {
if (PyErr_Occurred()) {
return NULL;
}
/* Otherwise, set up a new thread local context. */
tl_context = context_copy(default_context_template);
if (tl_context == NULL) {
return NULL;
}
CTX(tl_context)->status = 0;
/* Set up a new thread local context. */
tl_context = context_copy(default_context_template);
if (tl_context == NULL) {
return NULL;
}
CTX(tl_context)->status = 0;
if (PyDict_SetItem(dict, tls_context_key, tl_context) < 0) {
if (PyDict_SetItem(dict, tls_context_key, tl_context) < 0) {
Py_DECREF(tl_context);
return NULL;
}
Py_DECREF(tl_context);
return NULL;
}
Py_DECREF(tl_context);
/* refcount is 1 */
/* Cache the context of the current thread, assuming that it
* will be accessed several times before a thread switch. */
tstate = PyThreadState_GET();
if (tstate) {
cached_context = (PyDecContextObject *)tl_context;
cached_context->tstate = tstate;
}
/* Borrowed reference with refcount==1 */
return tl_context;
}
/* Return borrowed reference to thread local context. */
static PyObject *
current_context(void)
{
PyThreadState *tstate;
tstate = PyThreadState_GET();
if (cached_context && cached_context->tstate == tstate) {
return (PyObject *)cached_context;
}
return current_context_from_dict();
}
/* ctxobj := borrowed reference to the current context */
#define CURRENT_CONTEXT(ctxobj) \
ctxobj = current_context(); \
@ -1664,6 +1700,7 @@ PyDec_SetCurrentContext(PyObject *self UNUSED, PyObject *v)
Py_INCREF(v);
}
cached_context = NULL;
if (PyDict_SetItem(dict, tls_context_key, v) < 0) {
Py_DECREF(v);
return NULL;

9
Modules/_randommodule.c
View File

@ -228,16 +228,17 @@ random_seed(RandomObject *self, PyObject *args)
Py_INCREF(Py_None);
return Py_None;
}
/* If the arg is an int or long, use its absolute value; else use
* the absolute value of its hash code.
/* This algorithm relies on the number being unsigned.
* So: if the arg is a PyLong, use its absolute value.
* Otherwise use its hash value, cast to unsigned.
*/
if (PyLong_Check(arg))
n = PyNumber_Absolute(arg);
else {
Py_ssize_t hash = PyObject_Hash(arg);
Py_hash_t hash = PyObject_Hash(arg);
if (hash == -1)
goto Done;
n = PyLong_FromSsize_t(hash);
n = PyLong_FromSize_t((size_t)hash);
}
if (n == NULL)
goto Done;