ctypes help

[gianluca]

Hy,
I need help about use dll with ctypes. I've compiled my dll C library
and I copied it in c:\windows\syst em32. When I load it with
"myDLL=cdll.Loa dLibrary(find_l ibrary("myDLL.d ll"))" It seem all OK but
python don't see the dll function. with dir(myDLL) I've only this:
['_FuncPtr', '__class__', '__delattr__', '__dict__', '__doc__',
'__getattr__', '__getattribute __', '__getitem__', '__hash__',
'__init__', '__module__', '__new__', '__reduce__', '__reduce_ex__' ,
'__repr__', '__setattr__', '__str__', '__weakref__', '_handle',
'_name']

Could anybody help me

Thanks

Gianluca

[sturlamolden]

On May 23, 12:33 am, gianluca <geonom...@gmai l.comwrote:

Hy,
I need help about use dll with ctypes. I've compiled my dll C library
and I copied it in c:\windows\syst em32. When I load it with
"myDLL=cdll.Loa dLibrary(find_l ibrary("myDLL.d ll"))" It seem all OK but
python don't see the dll function. with dir(myDLL) I've only this:
['_FuncPtr', '__class__', '__delattr__', '__dict__', '__doc__',
'__getattr__', '__getattribute __', '__getitem__', '__hash__',
'__init__', '__module__', '__new__', '__reduce__', '__reduce_ex__' ,
'__repr__', '__setattr__', '__str__', '__weakref__', '_handle',
'_name']

I see nothing wrong here.

[Larry Bates]

gianluca wrote:

Hy,
I need help about use dll with ctypes. I've compiled my dll C library
and I copied it in c:\windows\syst em32. When I load it with
"myDLL=cdll.Loa dLibrary(find_l ibrary("myDLL.d ll"))" It seem all OK but
python don't see the dll function. with dir(myDLL) I've only this:
['_FuncPtr', '__class__', '__delattr__', '__dict__', '__doc__',
'__getattr__', '__getattribute __', '__getitem__', '__hash__',
'__init__', '__module__', '__new__', '__reduce__', '__reduce_ex__' ,
'__repr__', '__setattr__', '__str__', '__weakref__', '_handle',
'_name']

Could anybody help me

Thanks

Gianluca

Since it isn't python, dir can'd do much introspection on the object to produce
the type of output you desire. You have to know the functions (methods) that
you want to call in your dll and call them.

-Larry Bates

[gianluca]

On 23 Mag, 01:14, Larry Bates <larry.ba...@we bsafe.com`wrote :

gianluca wrote:

Hy,
I need help about use dll with ctypes. I've compiled my dll C library
and I copied it in c:\windows\syst em32. When I load it with
"myDLL=cdll.Loa dLibrary(find_l ibrary("myDLL.d ll"))" It seem all OK but
python don't see the dll function. with dir(myDLL) I've only this:
['_FuncPtr', '__class__', '__delattr__', '__dict__', '__doc__',
'__getattr__', '__getattribute __', '__getitem__', '__hash__',
'__init__', '__module__', '__new__', '__reduce__', '__reduce_ex__' ,
'__repr__', '__setattr__', '__str__', '__weakref__', '_handle',
'_name']

Could anybody help me

Thanks

Gianluca

Since it isn't python, dir can'd do much introspection on the object to produce
the type of output you desire. You have to know the functions (methods) that
you want to call in your dll and call them.

-Larry Bates

Yes, I know it but when I load a function (a=myDLL.myFUNC T()) I've an
exception like this:

Traceback (most recent call last):
File "<pyshell#1 8>", line 1, in <module>
myDLL.myFUNCT()
File "C:\Python25\li b\ctypes\__init __.py", line 353, in __getattr__
func = self.__getitem_ _(name)
File "C:\Python25\li b\ctypes\__init __.py", line 358, in __getitem__
func = self._FuncPtr(( name_or_ordinal , self))
AttributeError: function 'myFUNCT' not found

Thanks for help

[Marc 'BlackJack' Rintsch]

On Thu, 22 May 2008 21:55:41 -0700, gianluca wrote:

Yes, I know it but when I load a function (a=myDLL.myFUNC T()) I've an
exception like this:

Traceback (most recent call last):
File "<pyshell#1 8>", line 1, in <module>
myDLL.myFUNCT()
File "C:\Python25\li b\ctypes\__init __.py", line 353, in __getattr__
func = self.__getitem_ _(name)
File "C:\Python25\li b\ctypes\__init __.py", line 358, in __getitem__
func = self._FuncPtr(( name_or_ordinal , self))
AttributeError: function 'myFUNCT' not found

Then maybe the DLL doesn't contain a function called `myFUNCT`. Any
chance you compiled your C as C++ and name mangling kicked in?

Can you show a minimal C source for a DLL, how you compiled it, what you
did on the Python side to call it, and how it fails?

Ciao,
Marc 'BlackJack' Rintsch

[gianluca]

On 23 Mag, 07:48, Marc 'BlackJack' Rintsch <[e-mail] wrote:

On Thu, 22 May 2008 21:55:41 -0700, gianluca wrote:

Yes, I know it but when I load a function (a=myDLL.myFUNC T()) I've an
exception like this:

Traceback (most recent call last):
File "<pyshell#1 8>", line 1, in <module>
myDLL.myFUNCT()
File "C:\Python25\li b\ctypes\__init __.py", line 353, in __getattr__
func = self.__getitem_ _(name)
File "C:\Python25\li b\ctypes\__init __.py", line 358, in __getitem__
func = self._FuncPtr(( name_or_ordinal , self))
AttributeError: function 'myFUNCT' not found

Then maybe the DLL doesn't contain a function called `myFUNCT`. Any
chance you compiled your C as C++ and name mangling kicked in?

Can you show a minimal C source for a DLL, how you compiled it, what you
did on the Python side to call it, and how it fails?

Ciao,
Marc 'BlackJack' Rintsch

I've located my dll in c:\windows\syst em32 (in linux I aven't any
problem) and I compiled it with dev-c++. The source code is C standard
ANSII and is quite havy. If you like I can send it via mail (you can
realy at ge*******@gmail .com) . I've tryed to build a wrape with swig
olso with same code and I can access at all the function.
thanks
Gianluca

[Nick Craig-Wood]

gianluca <ge*******@gmai l.comwrote:

On 23 Mag, 07:48, Marc 'BlackJack' Rintsch <[e-mail] wrote:

On Thu, 22 May 2008 21:55:41 -0700, gianluca wrote:

Yes, I know it but when I load a function (a=myDLL.myFUNC T()) I've an
exception like this:

Traceback (most recent call last):
File "<pyshell#1 8>", line 1, in <module>
myDLL.myFUNCT()
File "C:\Python25\li b\ctypes\__init __.py", line 353, in __getattr__
func = self.__getitem_ _(name)
File "C:\Python25\li b\ctypes\__init __.py", line 358, in __getitem__
func = self._FuncPtr(( name_or_ordinal , self))
AttributeError: function 'myFUNCT' not found

Then maybe the DLL doesn't contain a function called `myFUNCT`. Any
chance you compiled your C as C++ and name mangling kicked in?

Can you show a minimal C source for a DLL, how you compiled it, what you
did on the Python side to call it, and how it fails?

Ciao,
Marc 'BlackJack' Rintsch

I've located my dll in c:\windows\syst em32 (in linux I aven't any
problem) and I compiled it with dev-c++. The source code is C standard
ANSII and is quite havy. If you like I can send it via mail (you can
realy at ge*******@gmail .com) . I've tryed to build a wrape with swig
olso with same code and I can access at all the function.

You can use objdump from mingw or cygwin to look inside the dll and
see exactly what it is exporting, eg

objdump -x OurSharedCodeLi brary.dll

This prints a great deal of stuff! In the middle you'll see

[snip]
The Export Tables (interpreted .rdata section contents)
[snip]
Ordinal/Name Pointer] Table
[ 0] OSCL_DEBUG_fake InitComplete
[ 1] OSCL_close
[ 2] OSCL_displayIde nt
[ 3] OSCL_getCurrent DynamicParams
[ 4] OSCL_getCurrent StaticParams
[ 5] OSCL_getErrorSt ring
[ 6] OSCL_getIdent
[snip]

This is a dll we used in a project, and those names exactly worked
with ctypes, eg some snips from the ctypes code

self.dll = cdll.LoadLibrar y("OurSharedCod eLibrary")
self.dll.OSCL_g etErrorString.r estype = c_char_p

def getErrorString( self, status):
return self.dll.OSCL_g etErrorString(c _int(status))

--
Nick Craig-Wood <ni**@craig-wood.com-- http://www.craig-wood.com/nick

[gianluca]

On 23 Mag, 12:30, Nick Craig-Wood <[e-mail]:

gianluca <geonom...@gmai l.comwrote:

On 23 Mag, 07:48, Marc 'BlackJack' Rintsch <[e-mail] wrote:

On Thu, 22 May 2008 21:55:41 -0700, gianluca wrote:
Yes, I know it but when I load a function (a=myDLL.myFUNC T()) I've an
exception like this:

Traceback (most recent call last):
File "<pyshell#1 8>", line 1, in <module>
myDLL.myFUNCT()
File "C:\Python25\li b\ctypes\__init __.py", line 353, in __getattr__
func = self.__getitem_ _(name)
File "C:\Python25\li b\ctypes\__init __.py", line 358, in __getitem__
func = self._FuncPtr(( name_or_ordinal , self))
AttributeError: function 'myFUNCT' not found

Then maybe the DLL doesn't contain a function called `myFUNCT`. Any
chance you compiled your C as C++ and name mangling kicked in?

Can you show a minimal C source for a DLL, how you compiled it, what you
did on the Python side to call it, and how it fails?

Ciao,
Marc 'BlackJack' Rintsch

I've located my dll in c:\windows\syst em32 (in linux I aven't any
problem) and I compiled it with dev-c++. The source code is C standard
ANSII and is quite havy. If you like I can send it via mail (you can
realy at geonom...@gmail .com) . I've tryed to build a wrape with swig
olso with same code and I can access at all the function.

You can use objdump from mingw or cygwin to look inside the dll and
see exactly what it is exporting, eg

objdump -x OurSharedCodeLi brary.dll

This prints a great deal of stuff! In the middle you'll see

[snip]
The Export Tables (interpreted .rdata section contents)
[snip]
Ordinal/Name Pointer] Table
[ 0] OSCL_DEBUG_fake InitComplete
[ 1] OSCL_close
[ 2] OSCL_displayIde nt
[ 3] OSCL_getCurrent DynamicParams
[ 4] OSCL_getCurrent StaticParams
[ 5] OSCL_getErrorSt ring
[ 6] OSCL_getIdent
[snip]

This is a dll we used in a project, and those names exactly worked
with ctypes, eg some snips from the ctypes code

self.dll = cdll.LoadLibrar y("OurSharedCod eLibrary")
self.dll.OSCL_g etErrorString.r estype = c_char_p

def getErrorString( self, status):
return self.dll.OSCL_g etErrorString(c _int(status))

--
Nick Craig-Wood <[e-mail]--http://www.craig-wood.com/nick

Thank you for help!
I've done all you suggest and I've a objdump output like this:
....
[ 86](sec 1)(fl 0x00)(ty 20)(scl 2) (nx 0) 0x00003755 _IsCoverRelD
[ 87](sec 1)(fl 0x00)(ty 20)(scl 2) (nx 0) 0x00003657 _IsCoverRelA
[ 88](sec 1)(fl 0x00)(ty 20)(scl 2) (nx 0) 0x000034f5 _IsCoverDX
[ 89](sec 1)(fl 0x00)(ty 20)(scl 2) (nx 0) 0x0000341b _IsCoverA
[ 90](sec 1)(fl 0x00)(ty 20)(scl 2) (nx 0) 0x00003072 _CoreRelD
[ 91](sec 1)(fl 0x00)(ty 20)(scl 2) (nx 0) 0x00002f5e _CoreRelA
....
my funtions are the __IsCoverRelD, __IsCoverRelA, etc but when I call
it (myLIB.__IsCove rRelA or myLIB.__IsCover RelA()) I've the same
problem.
Hy
gianluca

[Terry Reedy]

"gianluca" <ge*******@gmai l.comwrote in message
news:ce******** *************** ***********@e39 g2000hsf.google groups.com...
| Thank you for help!
| I've done all you suggest and I've a objdump output like this:
| ...
| [ 86](sec 1)(fl 0x00)(ty 20)(scl 2) (nx 0) 0x00003755 _IsCoverRelD
| [ 87](sec 1)(fl 0x00)(ty 20)(scl 2) (nx 0) 0x00003657 _IsCoverRelA
| [ 88](sec 1)(fl 0x00)(ty 20)(scl 2) (nx 0) 0x000034f5 _IsCoverDX
| [ 89](sec 1)(fl 0x00)(ty 20)(scl 2) (nx 0) 0x0000341b _IsCoverA
| [ 90](sec 1)(fl 0x00)(ty 20)(scl 2) (nx 0) 0x00003072 _CoreRelD
| [ 91](sec 1)(fl 0x00)(ty 20)(scl 2) (nx 0) 0x00002f5e _CoreRelA

The name above have one underscore.
| my funtions are the __IsCoverRelD, __IsCoverRelA, etc but when I call
| it (myLIB.__IsCove rRelA or myLIB.__IsCover RelA()) I've the same
| problem.

These all have two. So if that is what you actually did....

tjr