os.path
— 常见路径名操纵
¶
源代码： Lib/posixpath.py (为 POSIX)， Lib/ntpath.py (为 Windows NT)，和 Lib/macpath.py (为 Macintosh)
此模块实现一些有用路径名功能。要读取或写入文件，见
open()
，和要访问文件系统，见
os
module. The path parameters can be passed as either strings, or bytes. Applications are encouraged to represent file names as (Unicode) character strings. Unfortunately, some file names may not be representable as strings on Unix, so applications that need to support arbitrary file names on Unix should use bytes objects to represent path names. Vice versa, using bytes objects cannot represent all file names on Windows (in the standard
mbcs
encoding), hence Windows applications should use string objects to access all files.
Unlike a unix shell, Python does not do any
automatic
path expansions. Functions such as
expanduser()
and
expandvars()
can be invoked explicitly when an application desires shell-like path expansion. (See also the
glob
模块。)
另请参阅
pathlib
模块提供高级路径对象。
注意
All of these functions accept either only bytes or only string objects as their parameters. The result is an object of the same type, if a path or file name is returned.
注意
Since different operating systems have different path name conventions, there are several versions of this module in the standard library. The
os.path
module is always the path module suitable for the operating system Python is running on, and therefore usable for local paths. However, you can also import and use the individual modules if you want to manipulate a path that is
always
in one of the different formats. They all have the same interface:
posixpath
用于 UNIX 样式路径
ntpath
用于 Windows 路径
macpath
用于旧样式 MacOS 路径
os.path.
abspath
(
path
)
¶
Return a normalized absolutized version of the pathname
path
. On most platforms, this is equivalent to calling the function
normpath()
as follows:
normpath(join(os.getcwd(),
path))
.
3.6 版改变： 接受 像路径对象 .
os.path.
basename
(
path
)
¶
Return the base name of pathname
path
. This is the second element of the pair returned by passing
path
to the function
split()
. Note that the result of this function is different from the Unix
basename
program; where
basename
for
'/foo/bar/'
返回
'bar'
，
basename()
function returns an empty string (
''
).
3.6 版改变： 接受 像路径对象 .
os.path.
commonpath
(
paths
)
¶
Return the longest common sub-path of each pathname in the sequence
paths
. Raise ValueError if
paths
contains both absolute and relative pathnames, or if
paths
is empty. Unlike
commonprefix()
, this returns a valid path.
可用性：Unix Windows
3.5 版新增。
3.6 版改变： 接受序列的 像路径对象 .
os.path.
commonprefix
(
list
)
¶
Return the longest path prefix (taken character-by-character) that is a prefix of all paths in
list
。若
list
is empty, return the empty string (
''
).
注意
This function may return invalid paths because it works a character at a time. To obtain a valid path, see
commonpath()
.
>>> os.path.commonprefix(['/usr/lib', '/usr/local/lib'])
'/usr/l'
>>> os.path.commonpath(['/usr/lib', '/usr/local/lib'])
'/usr'
3.6 版改变： 接受 像路径对象 .
os.path.
dirname
(
path
)
¶
Return the directory name of pathname
path
. This is the first element of the pair returned by passing
path
to the function
split()
.
3.6 版改变： 接受 像路径对象 .
os.path.
exists
(
path
)
¶
返回
True
if
path
refers to an existing path or an open file descriptor. Returns
False
for broken symbolic links. On some platforms, this function may return
False
if permission is not granted to execute
os.stat()
on the requested file, even if the
path
physically exists.
3.3 版改变：
path
can now be an integer:
True
is returned if it is an open file descriptor,
False
否则。
3.6 版改变： 接受 像路径对象 .
os.path.
lexists
(
path
)
¶
返回
True
if
path
refers to an existing path. Returns
True
for broken symbolic links. Equivalent to
exists()
on platforms lacking
os.lstat()
.
3.6 版改变： 接受 像路径对象 .
os.path.
expanduser
(
path
)
¶
On Unix and Windows, return the argument with an initial component of
~
or
~user
replaced by that
user
’s home directory.
On Unix, an initial
~
is replaced by the environment variable
HOME
if it is set; otherwise the current user’s home directory is looked up in the password directory through the built-in module
pwd
. An initial
~user
is looked up directly in the password directory.
在 Windows，
HOME
and
USERPROFILE
will be used if set, otherwise a combination of
HOMEPATH
and
HOMEDRIVE
will be used. An initial
~user
is handled by stripping the last directory component from the created user path derived above.
If the expansion fails or if the path does not begin with a tilde, the path is returned unchanged.
3.6 版改变： 接受 像路径对象 .
os.path.
expandvars
(
path
)
¶
Return the argument with environment variables expanded. Substrings of the form
$name
or
${name}
are replaced by the value of environment variable
name
. Malformed variable names and references to non-existing variables are left unchanged.
在 Windows，
%name%
expansions are supported in addition to
$name
and
${name}
.
3.6 版改变： 接受 像路径对象 .
os.path.
getatime
(
path
)
¶
Return the time of last access of
path
. The return value is a number giving the number of seconds since the epoch (see the
time
module). Raise
OSError
if the file does not exist or is inaccessible.
若
os.stat_float_times()
返回
True
，结果是浮点数。
os.path.
getmtime
(
path
)
¶
Return the time of last modification of
path
. The return value is a number giving the number of seconds since the epoch (see the
time
module). Raise
OSError
if the file does not exist or is inaccessible.
若
os.stat_float_times()
返回
True
，结果是浮点数。
3.6 版改变： 接受 像路径对象 .
os.path.
getctime
(
path
)
¶
Return the system’s ctime which, on some systems (like Unix) is the time of the last metadata change, and, on others (like Windows), is the creation time for
path
. The return value is a number giving the number of seconds since the epoch (see the
time
module). Raise
OSError
if the file does not exist or is inaccessible.
3.6 版改变： 接受 像路径对象 .
os.path.
getsize
(
path
)
¶
Return the size, in bytes, of
path
。引发
OSError
if the file does not exist or is inaccessible.
3.6 版改变： 接受 像路径对象 .
os.path.
isabs
(
path
)
¶
返回
True
if
path
is an absolute pathname. On Unix, that means it begins with a slash, on Windows that it begins with a (back)slash after chopping off a potential drive letter.
3.6 版改变： 接受 像路径对象 .
os.path.
isfile
(
path
)
¶
返回
True
if
path
是
existing
regular file. This follows symbolic links, so both
islink()
and
isfile()
can be true for the same path.
3.6 版改变： 接受 像路径对象 .
os.path.
isdir
(
path
)
¶
返回
True
if
path
是
existing
directory. This follows symbolic links, so both
islink()
and
isdir()
can be true for the same path.
3.6 版改变： 接受 像路径对象 .
os.path.
islink
(
path
)
¶
返回
True
if
path
refers to an
existing
directory entry that is a symbolic link. Always
False
if symbolic links are not supported by the Python runtime.
3.6 版改变： 接受 像路径对象 .
os.path.
ismount
(
path
)
¶
返回
True
if pathname
path
是
mount point
: a point in a file system where a different file system has been mounted. On POSIX, the function checks whether
path
’s parent,
path/..
, is on a different device than
path
, or whether
path/..
and
path
point to the same i-node on the same device — this should detect mount points for all Unix and POSIX variants. On Windows, a drive letter root and a share UNC are always mount points, and for any other path
GetVolumePathName
is called to see if it is different from the input path.
3.4 版新增： Support for detecting non-root mount points on Windows.
3.6 版改变： 接受 像路径对象 .
os.path.
join
(
path
,
*paths
)
¶
Join one or more path components intelligently. The return value is the concatenation of
path
and any members of
*paths
with exactly one directory separator (
os.sep
) following each non-empty part except the last, meaning that the result will only end in a separator if the last part is empty. If a component is an absolute path, all previous components are thrown away and joining continues from the absolute path component.
On Windows, the drive letter is not reset when an absolute path component (e.g.,
r'\foo'
) is encountered. If a component contains a drive letter, all previous components are thrown away and the drive letter is reset. Note that since there is a current directory for each drive,
os.path.join("c:",
"foo")
represents a path relative to the current directory on drive
C:
(
c:foo
), not
c:\foo
.
3.6 版改变： 接受 像路径对象 for path and paths .
os.path.
normcase
(
path
)
¶
Normalize the case of a pathname. On Unix and Mac OS X, this returns the path unchanged; on case-insensitive filesystems, it converts the path to lowercase. On Windows, it also converts forward slashes to backward slashes. Raise a TypeError if the type of
path
不是
str
or
bytes
(直接或间接透过
os.PathLike
interface).
3.6 版改变： 接受 像路径对象 .
os.path.
normpath
(
path
)
¶
Normalize a pathname by collapsing redundant separators and up-level references so that
A//B
,
A/B/
,
A/./B
and
A/foo/../B
all become
A/B
. This string manipulation may change the meaning of a path that contains symbolic links. On Windows, it converts forward slashes to backward slashes. To normalize case, use
normcase()
.
3.6 版改变： 接受 像路径对象 .
os.path.
realpath
(
path
)
¶
Return the canonical path of the specified filename, eliminating any symbolic links encountered in the path (if they are supported by the operating system).
3.6 版改变： 接受 像路径对象 .
os.path.
relpath
(
path
,
start=os.curdir
)
¶
Return a relative filepath to path either from the current directory or from an optional start directory. This is a path computation: the filesystem is not accessed to confirm the existence or nature of path or start .
start
默认为
os.curdir
.
可用性：Unix Windows。
3.6 版改变： 接受 像路径对象 .
os.path.
samefile
(
path1
,
path2
)
¶
返回
True
if both pathname arguments refer to the same file or directory. This is determined by the device number and i-node number and raises an exception if an
os.stat()
call on either pathname fails.
可用性：Unix Windows。
3.2 版改变： 添加 Windows 支持。
3.4 版改变： Windows 现在使用与所有其它平台相同的实现。
3.6 版改变： 接受 像路径对象 .
os.path.
sameopenfile
(
fp1
,
fp2
)
¶
返回
True
if the file descriptors
fp1
and
fp2
refer to the same file.
可用性：Unix Windows。
3.2 版改变： 添加 Windows 支持。
3.6 版改变： 接受 像路径对象 .
os.path.
samestat
(
stat1
,
stat2
)
¶
返回
True
if the stat tuples
stat1
and
stat2
refer to the same file. These structures may have been returned by
os.fstat()
,
os.lstat()
，或
os.stat()
. This function implements the underlying comparison used by
samefile()
and
sameopenfile()
.
可用性：Unix Windows。
3.4 版改变： 添加 Windows 支持。
3.6 版改变： 接受 像路径对象 .
os.path.
split
(
path
)
¶
分割路径名
path
into a pair,
(head,
tail)
where
tail
is the last pathname component and
head
is everything leading up to that. The
tail
part will never contain a slash; if
path
ends in a slash,
tail
will be empty. If there is no slash in
path
,
head
will be empty. If
path
is empty, both
head
and
tail
are empty. Trailing slashes are stripped from
head
unless it is the root (one or more slashes only). In all cases,
join(head,
tail)
returns a path to the same location as
path
(but the strings may differ). Also see the functions
dirname()
and
basename()
.
3.6 版改变： 接受 像路径对象 .
os.path.
splitdrive
(
path
)
¶
分割路径名
path
into a pair
(drive,
tail)
where
drive
is either a mount point or the empty string. On systems which do not use drive specifications,
drive
will always be the empty string. In all cases,
drive
+
tail
will be the same as
path
.
On Windows, splits a pathname into drive/UNC sharepoint and relative path.
If the path contains a drive letter, drive will contain everything up to and including the colon. e.g.
splitdrive("c:/dir")
返回
("c:",
"/dir")
If the path contains a UNC path, drive will contain the host name and share, up to but not including the fourth separator. e.g.
splitdrive("//host/computer/dir")
返回
("//host/computer",
"/dir")
3.6 版改变： 接受 像路径对象 .
os.path.
splitext
(
path
)
¶
分割路径名
path
into a pair
(root,
ext)
这样
root
+
ext
==
path
，和
ext
is empty or begins with a period and contains at most one period. Leading periods on the basename are ignored;
splitext('.cshrc')
返回
('.cshrc',
'')
.
3.6 版改变： 接受 像路径对象 .
os.path.
splitunc
(
path
)
¶
从 3.3 版起弃用： 使用 splitdrive 代替。
分割路径名
path
into a pair
(unc,
rest)
so that
unc
is the UNC mount point (such as
r'\\host\mount'
), if present, and
rest
the rest of the path (such as
r'\path\file.ext'
). For paths containing drive letters,
unc
will always be the empty string.
可用性：Windows。
os.path.
supports_unicode_filenames
¶
True
if arbitrary Unicode strings can be used as file names (within limitations imposed by the file system).