For ease of use, is the way to go. The following example of ctypes is from actual code I've written (in Python 2.5). Define methods for each function of # the DLL that you wish to implement. # import os, sys import calldll from dynwin.windll import cstring, membuf class DLLInterface: '' class DLLInterface is used as a base class as a general interface class to Microsoft Windows DLLs. Is there a difference between the python-binaries with the gdal-core-setup and the libraries within the zip-files? I used the zip-files due to the rights-management on my desktop-computer. IPython imports a lot of libraries, and buried deep within that import tree, a windows specific flag imports win32com, which in turn imports pythoncom.The pythoncom import loads the library pythoncomXX.dll. (XX=36 or python version number). This has been, by far, the easiest way I've found for doing what you ask. Import ctypes # Load DLL into memory. HllDll = ctypes.WinDLL ('c: PComm ehlapi32.dll') # Set up prototype and parameters for the desired function call. # HLLAPI hllApiProto = ctypes.WINFUNCTYPE ( ctypes.c_int, # Return type. Ctypes.c_void_p, # Parameters 1. Ctypes.c_void_p, ctypes.c_void_p, ctypes.c_void_p) #. HllApiParams = (1, 'p1', 0), (1, 'p2', 0), (1, 'p3',0), (1, 'p4',0), # Actually map the call ('HLLAPI(.)') to a Python name. HllApi = hllApiProto (('HLLAPI', hllDll), hllApiParams) # This is how you can actually call the DLL function. # Set up the variables and call the Python name with them. P1 = ctypes.c_int (1) p2 = ctypes.c_char_p (sessionVar) p3 = ctypes.c_int (1) p4 = ctypes.c_int (0) hllApi (ctypes.byref (p1), p2, ctypes.byref (p3), ctypes.byref (p4)) The ctypes stuff has all the C-type data types ( int, char, short, void*, and so on) and can pass by value or reference. It can also return specific data types although my example doesn't do that (the HLL API returns values by modifying a variable passed by reference). In terms of the specific example shown above, IBM's EHLLAPI is a fairly consistent interface. All calls pass four void pointers (EHLLAPI sends the return code back through the fourth parameter, a pointer to an int so, while I specify int as the return type, I can safely ignore it) as per IBM's documentation. In other words, the C variant of the function would be: int hllApi (void *p1, void *p2, void *p3, void *p4) This makes for a single, simple ctypes function able to do anything the EHLLAPI library provides, but it's likely that other libraries will need a separate ctypes function set up per library function. Adobe flash player 10 debian download free. The return value from WINFUNCTYPE is a function prototype but you still have to set up more parameter information (over and above the types). Each tuple in hllApiParams has a parameter 'direction' (1 = input, 2 = output and so on), a parameter name and a default value - see the ctypes doco for details Once you have the prototype and parameter information, you can create a Python 'callable' hllApi with which to call the function. You simply create the needed variable ( p1 through p4 in my case) and call the function with them. @yughred, unfortunately, I left IBM quite a while ago so no longer have access to a ready PComm to test it against. From memory, the only error I ever saw from this was when trying to use a PSID that was already in use, but your error 9 hints at something more fundamental, possibly an environment setup issue. Sorry I can't help more, perhaps it would be worthwhile seeing if you can find logs somewhere, something that gives a little more info than 'a system error occurred':-) Other than that, the best I can do is suggest you recheck all parameters being sent to the function. – Jul 10 at 13:59. Has a very simple example of calling functions from a DLL file. Paraphrasing the details here for completeness: It's very easy to call a DLL function in Python. I have a self-made DLL file with two functions: add and sub which take two arguments. Add(a, b) returns addition of two numbers sub(a, b) returns substraction of two numbers The name of the DLL file will be 'demo.dll' Program: from ctypes import* # give location of dll mydll = cdll.LoadLibrary('C: demo.dll') result1= mydll.add(10,1) result2= mydll.sub(10,1) print 'Addition value:'+result1 print 'Substraction:'+result2 Output: Addition value:11 Substraction:9. • • New in Python version 2.5 is the ctypes, a foreign function library. It provides C-compatible data types and allows calling functions in DLLs or shared libraries. Using the ctypes module in Python allows ArcObjects code written in C++ to be used in a geoprocessing script tool. Using ctypes in Python allows you to easily change the parameters and types the script tool expects without having to recompile our C++ code. The ctypes module supports any C-callable function with basic data types, such as char, int, float, and double as well as structs and pointers. For more information on the ctypes module in Python 2.6.2, refer to. There are many benefits with calling a DLL from a Python script. You can leverage the finely grained ArcObjects classes in your geoprocessing tasks, your intellectual property is protected, and it is much easier to implement than having to use the IGPFunction2 and IGPFunctionFactory interfaces. You create your object in Python and call the execute method, passing in the required parameters from the script using the geoprocessing framework. How it works The steps are the following: Create a C++ Win32 project in Visual Studio 2008 that exports a simple function with the prototype. Int GpExecutetool ( char * parameter1, char * parameter2 ) Be sure to include the ArcGIS com directory in the project and import the ArcObjects.olb files. Create a script tool in a custom toolbox that validates the two parameters and passes them to the script. Your Python script will do the following: • Import arcpy and ctypes. • Get the parameters from the script tool. • Import the DLL into memory. • Get a pointer to the function in the DLL. • Specify the required argument types of functions exported from DLLs by setting the argtypes attribute as well as the return type. • Pass the parameters to the C++ code in the DLL. The details The C++ project (named GPToolAsSimpleDLL for this example) is a simple Win32 project that adds an AREA field to the feature class and calculates the value. The header file. Restaurant empire 2 patch francais pour. #ifdef GPTOOLASSIMPLEDLL_EXPORTS #define GPTOOLASSIMPLEDLL_API extern 'C'__declspec(dllexport) #else #define GPTOOLASSIMPLEDLL_API extern 'C'__declspec(dllimport) #endif GPTOOLASSIMPLEDLL_API int GPexecutetool ( char *, char * ); The GPToolAsSimpleDLL source file opens the specified polygon feature class and sets the specified field to the area of each polygon feature. Every geoprocessing function you write could be implemented with a simple C function entry point, all in the same DLL, along with script tool companions to expose each function to ArcToolbox. Import arcpy import ctypes # Get the parameters from the script tool dialog # shp = arcpy. GetParameterAsText ( 0 ) fieldName = arcpy. GetParameterAsText ( 1 ) # See if the field already exists in the feature class. # If not, add it. If len ( arcpy. ListFields ( shp, fieldName )) == 0: arcpy. AddField_management ( shp, fieldName, 'DOUBLE' ) # Import DLL into memory and get a pointer to the function # Note: be sure the DLL is in your Python search path # dll = ctypes. GPToolAsSimpleDLL perform_function = dll. GPExecutetool # Tell ctypes the function accepts two char* arguments # perform_function. Argtypes = [ ctypes. C_char_p, ctypes. C_char_p ] # Tell ctypes the function return type # perform_function. Restype = ctypes. C_int # Call the function in the DLL # retval = perform_function ( shp, fieldName ) # Check the return value. If a 0 returned, success! # if retval == 0: arcpy. AddMessage ( 'Success' ) elif retval == 1: arcpy. AddError ( 'Unable to open ' + shp ) elif retval == 2: arcpy. AddError ( 'Not a polygon feature class' ).
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