I need to interface with a windows DLL that has the following
signature
extern "C" void Foo( BSTR in, BSTR *out )
Code so far
>>from ctypes import * import comtypes LPBSTR = POINTER(comtype s.BSTR)
hdl = windll.MyDll.Fo o hdl.rettype = None hdl.argtype s = [comtypes.BSTR, LPBSTR]
inStr = comtypes.BSTR(u 'Some Silly String') out = comtypes.BSTR
hdl(inStr,byr ef(out))
Traceback (most recent call last):
File "<pyshell#1 4>", line 1, in <module>
hdl(inStr,byref (out))
TypeError: byref() argument must be a ctypes instance, not
'_ctypes.Simple Type'
Also tried the following
>>out = comtypes.BSTR(u '') p = pointer(out) hdl(inStr,p )
Traceback (most recent call last):
File "<pyshell#1 9>", line 1, in <module>
hdl(inStr,p)
ValueError: Procedure probably called with too many arguments (8 bytes
in excess)
Any feedback would be appreciated. 2 5858
mzdude wrote:
I need to interface with a windows DLL that has the following
signature
extern "C" void Foo( BSTR in, BSTR *out )
Code so far
>>>from ctypes import * import comtypes LPBSTR = POINTER(comtype s.BSTR)
hdl = windll.MyDll.Fo o hdl.rettyp e = None hdl.argtyp es = [comtypes.BSTR, LPBSTR]
inStr = comtypes.BSTR(u 'Some Silly String') out = comtypes.BSTR
out = comtypes.BSTR()
>>>hdl(inStr,by ref(out))
Traceback (most recent call last):
File "<pyshell#1 4>", line 1, in <module>
hdl(inStr,byref (out))
TypeError: byref() argument must be a ctypes instance, not
'_ctypes.Simple Type'
comtypes.BSTR is a type; the type error makes clear you need
an instance, as above.
Also tried the following
>>>out = comtypes.BSTR(u '') p = pointer(out) hdl(inStr, p)
Traceback (most recent call last):
File "<pyshell#1 9>", line 1, in <module>
hdl(inStr,p)
ValueError: Procedure probably called with too many arguments (8 bytes
in excess)
This likely indicates that the DLL is using the C calling convention
and not the stdcall calling convention. Use CDLL rather than WinDLL
to load the DLL.
You might like to join the ctypes-users mailing list at sourceforge.
--
-------------------------------------------------------------------------
Andrew I MacIntyre "These thoughts are mine alone..."
E-mail: an*****@bullsey e.apana.org.au (pref) | Snail: PO Box 370 an*****@pcug.or g.au (alt) | Belconnen ACT 2616
Web: http://www.andymac.org/ | Australia
On Jul 10, 6:15*am, Andrew MacIntyre <andy...@bullse ye.apana.org.au >
wrote:
<snip>
This likely indicates that the DLL is using the C calling convention
and not the stdcall calling convention. *Use CDLL rather than WinDLL
to load the DLL.
using cdll got me over the calling hurdle. However, I'm not seeing the
returned BSTR.
You might like to join the ctypes-users mailing list at sourceforge.
I did, thanks. This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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