ctypes help

Collapse
This topic is closed.
X
X
Collapse
 
  • Page of 1
  • Time
  • Show
Clear All
new posts
Previous template Next
  • gianluca
    #1

    ctypes help

    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
    Tags: None
    • sturlamolden
      #2
      Re: ctypes help

      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.






        Comment

        • Larry Bates
          #3
          Re: ctypes help

          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

            Comment

            • gianluca
              #4
              Re: ctypes help

              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

                Comment

                • Marc 'BlackJack' Rintsch
                  #5
                  Re: ctypes help

                  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

                    Comment

                    • gianluca
                      #6
                      Re: ctypes help

                      On 23 Mag, 07:48, Marc 'BlackJack' Rintsch <bj_...@gmx.net 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 geonomica@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

                        Comment

                        • Nick Craig-Wood
                          #7
                          Re: ctypes help

                          gianluca <geonomica@gmai l.comwrote:
                          On 23 Mag, 07:48, Marc 'BlackJack' Rintsch <bj_...@gmx.net 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 geonomica@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 <nick@craig-wood.com-- http://www.craig-wood.com/nick

                            Comment

                            • gianluca
                              #8
                              Re: ctypes help

                              On 23 Mag, 12:30, Nick Craig-Wood <n...@craig-wood.comwrote:
                              gianluca <geonom...@gmai l.comwrote:
                              On 23 Mag, 07:48, Marc 'BlackJack' Rintsch <bj_...@gmx.net 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 <n...@craig-wood.com--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

                                Comment

                                • Terry Reedy
                                  #9
                                  Re: ctypes help


                                  "gianluca" <geonomica@gmai l.comwrote in message
                                  news:ce293364-7aef-4c43-8504-5ae353c49406@e3 9g2000hsf.googl egroups.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



                                    Comment

                                    Previous template Next
                                    Working...