Call C function from C#

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C

C#

DLL

I am building an application where I need to integrate Dynamic Link Library runtime in c#. I am facing problem in calling one C function from C#.

DLL Function:

typedef void *JCCP_PROPERTY_HANDLE;
typedef void *JCCP_HANDLE;

JCCP_RESULT  __JCCP_FUNCTION__ jccpGetProperty(
    JCCP_HANDLE hjccp,
    const char *name,
    JCCP_PROPERTY_HANDLE *phproperty);

In Function Definition File:

_jccpGetProperty @49

Usage- C example:

JCCP_HANDLE m_hjccp = jccpAllocateHandle();
JCCP_PROPERTY_HANDLE hprop;
jccpGetProperty(m_hjccp, name, &hprop);

If this function executes successfully, It return 0.

Now I want to call this function (jccpGetProperty) in C#, but I dont know how to call this function in C#.

I have tried so far:

Declaration:

IntPtr hjccp;

     [DllImport(DLL_NAME, EntryPoint = "_jccpAllocateHandle", CallingConvention = CallingConvention.Cdecl)]

     [DllImport(DLL_NAME, EntryPoint = "_jccpGetProperty", CallingConvention = CallingConvention.Cdecl), UnmanagedFunctionPointer(CallingConvention.Cdecl)]
            public static extern IntPtr jccpGetProperty(IntPtr hjccp, string name, ref IntPtr handle);

In Main Function:

hjccp = jccpAllocateHandle();
IntPtr handle = IntPtr.Zero;
var result = jccpGetProperty(hjccp, "tag", ref handle);

I dont get any exception but I dont get 0 in response, I get 17 in response which is request discarded code. Can anybody guide me that how to call jccpGetProperty() in C# properly?
I am confused that how can I send third parameter to jccpGetProperty function through C#.

Thanks.