加载的dll的路径是什么？

Question

我在 Cygwin 下加载了一个dllwithctypes以下内容：

import ctypes
ctypes.cdll.LoadLibrary('foo.dll')

如何获得我的dll的绝对路径？

问题是我完全不知道 dll 所在的位置。我可以联系以下内容以获取此信息吗？

subprocess.Popen(["which", lib], stdout=subprocess.PIPE).stdout.read().strip()

Answer 1

在Unix中，加载的共享库的路径可以通过调用dladdr库中符号的地址（例如函数）来确定。

例子：

import ctypes
import ctypes.util

libdl = ctypes.CDLL(ctypes.util.find_library('dl'))

class Dl_info(ctypes.Structure):
    _fields_ = (('dli_fname', ctypes.c_char_p),
                ('dli_fbase', ctypes.c_void_p),
                ('dli_sname', ctypes.c_char_p),
                ('dli_saddr', ctypes.c_void_p))

libdl.dladdr.argtypes = (ctypes.c_void_p, ctypes.POINTER(Dl_info))

if __name__ == '__main__':
    import sys

    info = Dl_info()
    result = libdl.dladdr(libdl.dladdr, ctypes.byref(info))

    if result and info.dli_fname:
        libdl_path = info.dli_fname.decode(sys.getfilesystemencoding())
    else:
        libdl_path = u'Not Found'

    print(u'libdl path: %s' % libdl_path)

输出：

import ctypes
import ctypes.util

libdl = ctypes.CDLL(ctypes.util.find_library('dl'))

class Dl_info(ctypes.Structure):
    _fields_ = (('dli_fname', ctypes.c_char_p),
                ('dli_fbase', ctypes.c_void_p),
                ('dli_sname', ctypes.c_char_p),
                ('dli_saddr', ctypes.c_void_p))

libdl.dladdr.argtypes = (ctypes.c_void_p, ctypes.POINTER(Dl_info))

if __name__ == '__main__':
    import sys

    info = Dl_info()
    result = libdl.dladdr(libdl.dladdr, ctypes.byref(info))

    if result and info.dli_fname:
        libdl_path = info.dli_fname.decode(sys.getfilesystemencoding())
    else:
        libdl_path = u'Not Found'

    print(u'libdl path: %s' % libdl_path)