Re: Ctypes Error: Why can't it find the DLL.


Mudcat wrote:


So then I use the find_library function, and it finds it:

find_library('arapi51.dll')
'C:\\WINNT\\system32\\arapi51.dll'


Notice it's escaped the '\' character.

At that point I try to use the LoadLibrary function, but it still can't
find it:

windll.LoadLibrary('C:\WINNT\system32\arapi51.dll')
Traceback (most recent call last):
File "<interactive input>", line 1, in ?
File "C:\Python24\Lib\site-packages\ctypes\__init__.py", line 395, in
LoadLibrary
return self._dlltype(name)
File "C:\Python24\Lib\site-packages\ctypes\__init__.py", line 312, in
__init__
self._handle = _dlopen(self._name, mode)
WindowsError: [Errno 126] The specified module could not be found

What am I doing wrong? [snip]

You need to use either
windll.LoadLibrary(r'c:\winnt\system32\arapi51.dll') or escape the \'s
as the find_library function did. You're getting caught out by \a which
is the alert/bell character. \w and \s aren't valid escape sequences so
you get away with them. I'm guessing it's worked before because you've
been lucky.

Works fine!:
'C:\winnt\system32\smtpctrs.dll'
'C:\\winnt\\system32\\smtpctrs.dll'

Uh oh, escaped:
'C:\winnt\system32\arapi51.dll'
'C:\\winnt\\system32\x07rapi51.dll'

Jon.

.

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