Go Premium for a chance to win a PS4. Enter to Win

x
?
Solved

Callback functions ?

Posted on 1998-12-06
1
Medium Priority
?
174 Views
Last Modified: 2010-04-15
How can functions in a C DLL call methods/functions in the calling application.For example: a method called fnAdd(..) which resides in a DLL neeeds to take dynamic data from the user( interaction with the user ). Is it possible by passing to the dll a function name ( this function can be called by using the win api GetProcAddress )which it can call to take new data from the user.
Is there a specific way to pas such function names ?
0
Comment
Question by:shayad
1 Comment
 
LVL 12

Accepted Solution

by:
rwilson032697 earned 200 total points
ID: 1254911
Simply pass a pointer to the function in the application to the dll like so (second arg is a pointer to a function taking two int args returning an int.

extern "C" ADLLFunc(int arg1, (int)(int, int) *Arg2)
{
//...

if ((*arg2)(1, 2)) // call the callback function
{
 // ...
}
//...
}

My syntax declaration may be a little rusty but you get the picture...

Cheers,

Raymond.
0

Featured Post

Industry Leaders: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Have you thought about creating an iPhone application (app), but didn't even know where to get started? Here's how: ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ Important pre-programming comments: I’ve never tri…
Examines three attack vectors, specifically, the different types of malware used in malicious attacks, web application attacks, and finally, network based attacks.  Concludes by examining the means of securing and protecting critical systems and inf…
The goal of this video is to provide viewers with basic examples to understand how to use strings and some functions related to them in the C programming language.
Video by: Grant
The goal of this video is to provide viewers with basic examples to understand and use nested-loops in the C programming language.
Suggested Courses

877 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question