有谁知道从 Python 跨 win32 版本创建/读取符号链接的方法？理想情况下，应该有最少数量的平台特定代码，因为我需要我的应用程序是跨平台的。
【问题讨论】：
os.symlink？在 Windows 10 上为我工作（需要以管理员身份运行）。
标签： python winapi symlink pywin32
NTFS 文件系统有连接点，我想你可以使用它们，你可以使用 python win32 API 模块，例如
import win32file
win32file.CreateSymbolicLink(fileSrc, fileTarget, 1)
如果你不想依赖win32API模块，你可以随时使用ctypes直接调用CreateSymbolicLink win32 API 比如
import ctypes
kdll = ctypes.windll.LoadLibrary("kernel32.dll")
kdll.CreateSymbolicLinkA("d:\\test.txt", "d:\\test_link.txt", 0)
MSDN (http://msdn.microsoft.com/en-us/library/aa363866(VS.85).aspx) 说最低支持的客户端是 Windows Vista
另外：这也适用于目录（用第三个参数表示）。有了 unicode 支持，它看起来像这样：
kdll.CreateSymbolicLinkW(UR"D:\testdirLink", UR"D:\testdir", 1)
【讨论】：
..A Windows API，而是使用..W (Unicode) - 每次 - 即使在这样的例子中。
win32file.CreateSymbolicLink 显示的参数名称有点混乱。对于那些想知道的人，第一个是要创建的链接的名称，第二个是它应该链接到的路径。
win32file.CreateSymboleLink 上的最后一个参数应该是 1 表示目录，0 表示文件。
kernel32.dll 加载到进程中。无需明确说明。
os.symlink 在 Python 3.3 上使用 Windows 8.1 和 NTFS 文件系统。
【讨论】：
或者如果你想使用pywin32，你可以使用前面所说的方法，阅读，使用：
from win32file import *
from winioctlcon import FSCTL_GET_REPARSE_POINT
__all__ = ['islink', 'readlink']
# Win32file doesn't seem to have this attribute.
FILE_ATTRIBUTE_REPARSE_POINT = 1024
# To make things easier.
REPARSE_FOLDER = (FILE_ATTRIBUTE_DIRECTORY | FILE_ATTRIBUTE_REPARSE_POINT)
# For the parse_reparse_buffer function
SYMBOLIC_LINK = 'symbolic'
MOUNTPOINT = 'mountpoint'
GENERIC = 'generic'
def islink(fpath):
""" Windows islink implementation. """
if GetFileAttributes(fpath) & REPARSE_FOLDER == REPARSE_FOLDER:
return True
return False
def parse_reparse_buffer(original, reparse_type=SYMBOLIC_LINK):
""" Implementing the below in Python:
typedef struct _REPARSE_DATA_BUFFER {
ULONG ReparseTag;
USHORT ReparseDataLength;
USHORT Reserved;
union {
struct {
USHORT SubstituteNameOffset;
USHORT SubstituteNameLength;
USHORT PrintNameOffset;
USHORT PrintNameLength;
ULONG Flags;
WCHAR PathBuffer[1];
} SymbolicLinkReparseBuffer;
struct {
USHORT SubstituteNameOffset;
USHORT SubstituteNameLength;
USHORT PrintNameOffset;
USHORT PrintNameLength;
WCHAR PathBuffer[1];
} MountPointReparseBuffer;
struct {
UCHAR DataBuffer[1];
} GenericReparseBuffer;
} DUMMYUNIONNAME;
} REPARSE_DATA_BUFFER, *PREPARSE_DATA_BUFFER;
"""
# Size of our data types
SZULONG = 4 # sizeof(ULONG)
SZUSHORT = 2 # sizeof(USHORT)
# Our structure.
# Probably a better way to iterate a dictionary in a particular order,
# but I was in a hurry, unfortunately, so I used pkeys.
buffer = {
'tag' : SZULONG,
'data_length' : SZUSHORT,
'reserved' : SZUSHORT,
SYMBOLIC_LINK : {
'substitute_name_offset' : SZUSHORT,
'substitute_name_length' : SZUSHORT,
'print_name_offset' : SZUSHORT,
'print_name_length' : SZUSHORT,
'flags' : SZULONG,
'buffer' : u'',
'pkeys' : [
'substitute_name_offset',
'substitute_name_length',
'print_name_offset',
'print_name_length',
'flags',
]
},
MOUNTPOINT : {
'substitute_name_offset' : SZUSHORT,
'substitute_name_length' : SZUSHORT,
'print_name_offset' : SZUSHORT,
'print_name_length' : SZUSHORT,
'buffer' : u'',
'pkeys' : [
'substitute_name_offset',
'substitute_name_length',
'print_name_offset',
'print_name_length',
]
},
GENERIC : {
'pkeys' : [],
'buffer': ''
}
}
# Header stuff
buffer['tag'] = original[:SZULONG]
buffer['data_length'] = original[SZULONG:SZUSHORT]
buffer['reserved'] = original[SZULONG+SZUSHORT:SZUSHORT]
original = original[8:]
# Parsing
k = reparse_type
for c in buffer[k]['pkeys']:
if type(buffer[k][c]) == int:
sz = buffer[k][c]
bytes = original[:sz]
buffer[k][c] = 0
for b in bytes:
n = ord(b)
if n:
buffer[k][c] += n
original = original[sz:]
# Using the offset and length's grabbed, we'll set the buffer.
buffer[k]['buffer'] = original
return buffer
def readlink(fpath):
""" Windows readlink implementation. """
# This wouldn't return true if the file didn't exist, as far as I know.
if not islink(fpath):
return None
# Open the file correctly depending on the string type.
handle = CreateFileW(fpath, GENERIC_READ, 0, None, OPEN_EXISTING, FILE_FLAG_OPEN_REPARSE_POINT, 0) \
if type(fpath) == unicode else \
CreateFile(fpath, GENERIC_READ, 0, None, OPEN_EXISTING, FILE_FLAG_OPEN_REPARSE_POINT, 0)
# MAXIMUM_REPARSE_DATA_BUFFER_SIZE = 16384 = (16*1024)
buffer = DeviceIoControl(handle, FSCTL_GET_REPARSE_POINT, None, 16*1024)
# Above will return an ugly string (byte array), so we'll need to parse it.
# But first, we'll close the handle to our file so we're not locking it anymore.
CloseHandle(handle)
# Minimum possible length (assuming that the length of the target is bigger than 0)
if len(buffer) < 9:
return None
# Parse and return our result.
result = parse_reparse_buffer(buffer)
offset = result[SYMBOLIC_LINK]['substitute_name_offset']
ending = offset + result[SYMBOLIC_LINK]['substitute_name_length']
rpath = result[SYMBOLIC_LINK]['buffer'][offset:ending].replace('\x00','')
if len(rpath) > 4 and rpath[0:4] == '\\??\\':
rpath = rpath[4:]
return rpath
def realpath(fpath):
from os import path
while islink(fpath):
rpath = readlink(fpath)
if not path.isabs(rpath):
rpath = path.abspath(path.join(path.dirname(fpath), rpath))
fpath = rpath
return fpath
def example():
from os import system, unlink
system('cmd.exe /c echo Hello World > test.txt')
system('mklink test-link.txt test.txt')
print 'IsLink: %s' % islink('test-link.txt')
print 'ReadLink: %s' % readlink('test-link.txt')
print 'RealPath: %s' % realpath('test-link.txt')
unlink('test-link.txt')
unlink('test.txt')
if __name__=='__main__':
example()
根据您的需要调整 CreateFile 中的属性，但对于正常情况，它应该可以工作。随意改进它。
如果您使用 MOUNTPOINT 而不是 SYMBOLIC_LINK，它也应该适用于文件夹连接。
你可以检查一下
sys.getwindowsversion()[0] >= 6
如果你把它放到你要发布的东西中，因为这种形式的符号链接只在 Vista+ 上受支持。
【讨论】：
islink 的此实现将返回 True。
在子进程中使用 mklink 命令创建链接。
from subprocess import call
call(['mklink', 'LINK', 'TARGET'], shell=True)
【讨论】：
问题是，如解释，例如here，Windows 自己对符号链接功能的支持因 Windows 版本而异，例如在 Vista（有很多工作）中，您可以获得比 XP 或 2000 更多的功能（在其他 win32 版本上没有 AFAIK）。或者您可以使用快捷方式，它们当然有自己的一组限制，并且并不“真正”等同于 Unix 符号链接。因此，您必须准确指定您需要哪些功能，您愿意在跨 Win32 操作的祭坛上牺牲多少功能等等——然后，我们可以制定出如何实现您选择的折衷方案ctypes 或 win32all 的电话……从某种意义上说，这是最少的。
【讨论】：
我将以下内容放入 Lib/site-packages/sitecustomize.py
import os
__CSL = None
def symlink(source, link_name):
'''symlink(source, link_name)
Creates a symbolic link pointing to source named link_name'''
global __CSL
if __CSL is None:
import ctypes
csl = ctypes.windll.kernel32.CreateSymbolicLinkW
csl.argtypes = (ctypes.c_wchar_p, ctypes.c_wchar_p, ctypes.c_uint32)
csl.restype = ctypes.c_ubyte
__CSL = csl
flags = 0
if source is not None and os.path.isdir(source):
flags = 1
if __CSL(link_name, source, flags) == 0:
raise ctypes.WinError()
os.symlink = symlink
【讨论】：
Juntalis 的代码不处理 Unicode，所以我将其修改为使用 ctypes 并使用 struct 对其进行了简化。我还查阅了Using a struct as a function argument with the python ctypes module的代码
import os, ctypes, struct
from ctypes import windll, wintypes
FSCTL_GET_REPARSE_POINT = 0x900a8
FILE_ATTRIBUTE_READONLY = 0x0001
FILE_ATTRIBUTE_HIDDEN = 0x0002
FILE_ATTRIBUTE_DIRECTORY = 0x0010
FILE_ATTRIBUTE_NORMAL = 0x0080
FILE_ATTRIBUTE_REPARSE_POINT = 0x0400
GENERIC_READ = 0x80000000
GENERIC_WRITE = 0x40000000
OPEN_EXISTING = 3
FILE_READ_ATTRIBUTES = 0x80
FILE_FLAG_OPEN_REPARSE_POINT = 0x00200000
INVALID_HANDLE_VALUE = wintypes.HANDLE(-1).value
INVALID_FILE_ATTRIBUTES = 0xFFFFFFFF
FILE_FLAG_OPEN_REPARSE_POINT = 2097152
FILE_FLAG_BACKUP_SEMANTICS = 33554432
# FILE_FLAG_OPEN_REPARSE_POINT | FILE_FLAG_BACKUP_SEMANTI
FILE_FLAG_REPARSE_BACKUP = 35651584
GetFileAttributes = windll.kernel32.GetFileAttributesW
_CreateFileW = windll.kernel32.CreateFileW
_DevIoCtl = windll.kernel32.DeviceIoControl
_DevIoCtl.argtypes = [
wintypes.HANDLE, #HANDLE hDevice
wintypes.DWORD, #DWORD dwIoControlCode
wintypes.LPVOID, #LPVOID lpInBuffer
wintypes.DWORD, #DWORD nInBufferSize
wintypes.LPVOID, #LPVOID lpOutBuffer
wintypes.DWORD, #DWORD nOutBufferSize
ctypes.POINTER(wintypes.DWORD), #LPDWORD lpBytesReturned
wintypes.LPVOID] #LPOVERLAPPED lpOverlapped
_DevIoCtl.restype = wintypes.BOOL
def islink(path):
assert os.path.isdir(path), path
if GetFileAttributes(path) & FILE_ATTRIBUTE_REPARSE_POINT:
return True
else:
return False
def DeviceIoControl(hDevice, ioControlCode, input, output):
# DeviceIoControl Function
# http://msdn.microsoft.com/en-us/library/aa363216(v=vs.85).aspx
if input:
input_size = len(input)
else:
input_size = 0
if isinstance(output, int):
output = ctypes.create_string_buffer(output)
output_size = len(output)
assert isinstance(output, ctypes.Array)
bytesReturned = wintypes.DWORD()
status = _DevIoCtl(hDevice, ioControlCode, input,
input_size, output, output_size, bytesReturned, None)
print "status(%d)" % status
if status != 0:
return output[:bytesReturned.value]
else:
return None
def CreateFile(path, access, sharemode, creation, flags):
return _CreateFileW(path, access, sharemode, None, creation, flags, None)
SymbolicLinkReparseFormat = "LHHHHHHL"
SymbolicLinkReparseSize = struct.calcsize(SymbolicLinkReparseFormat);
def readlink(path):
""" Windows readlink implementation. """
# This wouldn't return true if the file didn't exist, as far as I know.
assert islink(path)
assert type(path) == unicode
# Open the file correctly depending on the string type.
hfile = CreateFile(path, GENERIC_READ, 0, OPEN_EXISTING,
FILE_FLAG_REPARSE_BACKUP)
# MAXIMUM_REPARSE_DATA_BUFFER_SIZE = 16384 = (16*1024)
buffer = DeviceIoControl(hfile, FSCTL_GET_REPARSE_POINT, None, 16384)
CloseHandle(hfile)
# Minimum possible length (assuming length of the target is bigger than 0)
if not buffer or len(buffer) < 9:
return None
# Parse and return our result.
# typedef struct _REPARSE_DATA_BUFFER {
# ULONG ReparseTag;
# USHORT ReparseDataLength;
# USHORT Reserved;
# union {
# struct {
# USHORT SubstituteNameOffset;
# USHORT SubstituteNameLength;
# USHORT PrintNameOffset;
# USHORT PrintNameLength;
# ULONG Flags;
# WCHAR PathBuffer[1];
# } SymbolicLinkReparseBuffer;
# struct {
# USHORT SubstituteNameOffset;
# USHORT SubstituteNameLength;
# USHORT PrintNameOffset;
# USHORT PrintNameLength;
# WCHAR PathBuffer[1];
# } MountPointReparseBuffer;
# struct {
# UCHAR DataBuffer[1];
# } GenericReparseBuffer;
# } DUMMYUNIONNAME;
# } REPARSE_DATA_BUFFER, *PREPARSE_DATA_BUFFER;
# Only handle SymbolicLinkReparseBuffer
(tag, dataLength, reserver, SubstituteNameOffset, SubstituteNameLength,
PrintNameOffset, PrintNameLength,
Flags) = struct.unpack(SymbolicLinkReparseFormat,
buffer[:SymbolicLinkReparseSize])
print tag, dataLength, reserver, SubstituteNameOffset, SubstituteNameLength
start = SubstituteNameOffset + SymbolicLinkReparseSize
actualPath = buffer[start : start + SubstituteNameLength].decode("utf-16")
# This utf-16 string is null terminated
index = actualPath.find(u"\0")
assert index > 0
if index > 0:
actualPath = actualPath[:index]
if actualPath.startswith(u"?\\"):
return actualPath[2:]
else:
return actualPath
【讨论】：
正如另一个答案中提到的，使用 subprocess.call 可能是 Windows 的最佳选择。但是直接调用 'mklink' 可能会导致：
[WinError 2] 系统找不到指定的文件
在 Windows Server 2016 上，我能够使以下内容适用于文件：
import subprocess
subprocess.call(['cmd', '/c', 'mklink', '<path_for_symlink>', '<path_for_file>'])
根据 mklink 文档更改上面的开关。
【讨论】：
尝试在 Windows 中创建符号链接我总是得到错误
A required privilege is not held by the client
但是我在使用此代码创建快捷方式时成功
import win32com.client
import pythoncom
import os
def create_shortcut(original_filepath, shortcut_filepath):
shell = win32com.client.Dispatch("WScript.Shell")
shortcut = shell.CreateShortCut(shortcut_filepath)
shortcut.Targetpath = original_filepath
shortcut.WindowStyle = 7
shortcut.save()
create_shortcut(r'C:\Users\xxx\Desktop\test.jpg',
r'C:\Users\xxx\Desktop\test.lnk')
注意：确保快捷方式以“.lnk”结尾
【讨论】：
这里是包含 kernel32.dll 的所有方法的链接
http://www.geoffchappell.com/studies/windows/win32/kernel32/api/
我在 Windows xp sp3 上使用了 CreateHardLinkA，它成功了！
导入 ctypes 如果 os.path.exists(link_file): os.remove(link_file)
dll = ctypes.windll.LoadLibrary("kernel32.dll")
dll.CreateHardLinkA(link_file, _log_filename, 0)
【讨论】：