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Passing variable arguments to ctypes function of C++

I have a problem when i pass variable arguments to ctypes function from HTML/JS->python in pyramid f/w -->C++

For example my http Get Call wil be as below:

PHP Code:




type: "GET", 
        async:   false, 
        url: "/web/NewModel/getValues?count=2&parameters=Param1,Param2", 
        success: function(data){ 
            alert(data.GetValue)

python base code

Code:

def get_Multiple_Xpaths(request):

        count = int(request.params['count'])

        requests=[]

        requests = request.params['parameters'].split(',')

        print 'count:%s' % (count)

        data=wrapperClass.getMultipleValues(count , *requests)

        print 'Final Data:%s' % (data)

        return {'Get':data}

I/F Python between python and C++

Code:

from ctypes import *

so = cdll.LoadLibrary(***)

funcHandle = so.CallC++Function

funcHandle.restype = c_char_p

def getMultipleValues(cls, count, *args):

                print 'count:%s' % (count)

                print 'Length of tuple:%s' %str(len(args))

                for a in args:

                        print 'Wrapper Param:%s' % (a)

                value=funcHandle(count, "Find" , *args) -->C++ debug prints parameters as empty. I tried to use str(*args) but it works only if *args actually has 1 argument. For multiple, it throws a type error.

                print 'Wrapper Value:%s' % (value)  ---->Returns Empty

                return value

The problem seems to be when i pass *args between 2 python functions, it is getting the values fine(when i print the values in getMultipleValues Function it prints fine). However the funcHandle Call which i use, the C++ doesnt get any value for *args which is being passed.

If i run a test program with funcHandle(count, "Find" , "parameter1" , "parameter2"), it gets the values fine.

Please advice me on what i am doing wrong here. My requirement is to pass the function with variable number of arguments as mentioned in the previous line so that C++ functions can access and process whatever it needs to. Thanks in advance. Cheers.

Quote:

Originally Posted by prasanthhs (Post 4749627)

I have a problem when i pass variable arguments to ctypes function from HTML/JS->python in pyramid f/w -->C++

For example my http Get Call wil be as below:

PHP Code:




type: "GET", 
        async:   false, 
        url: "/web/NewModel/getValues?count=2&parameters=Param1,Param2", 
        success: function(data){ 
            alert(data.GetValue)

python base code

Code:

def get_Multiple_Xpaths(request):

        count = int(request.params['count'])

        requests=[]

        requests = request.params['parameters'].split(',')

        print 'count:%s' % (count)

        data=wrapperClass.getMultipleValues(count , *requests)

        print 'Final Data:%s' % (data)

        return {'Get':data}

I/F Python between python and C++

Code:

from ctypes import *

so = cdll.LoadLibrary(***)

funcHandle = so.CallC++Function

funcHandle.restype = c_char_p

def getMultipleValues(cls, count, *args):

                print 'count:%s' % (count)

                print 'Length of tuple:%s' %str(len(args))

                for a in args:

                        print 'Wrapper Param:%s' % (a)

                value=funcHandle(count, "Find" , *args) -->C++ debug prints parameters as empty. I tried to use str(*args) but it works only if *args actually has 1 argument. For multiple, it throws a type error.

                print 'Wrapper Value:%s' % (value)  ---->Returns Empty

                return value

Any ideas guys..help me here !!