Abnormal termination of program? [C]

[riechan]

Hi guys, quick question. I'm getting the "abnormal termination of program" when I'm trying to terminate my C program. I'm not sure why this is happening though (sorry, still a beginner when it comes to programming...)

main() {
        ...	
	while(opt!=4){
		opt = menu();
		switch(opt){
			case 4:
				clrscr();
				printf("Exiting application...");
				exit(0);
				getch();
				break;
        ...
		}
	}
}

void exit(){
	return;
}

[riechan]

So I made a few changes to the program:

...
			case 4:
				clrscr();
				printf("Exiting application...");
				getch();
				exit();
...
void exit(){
	return 0;
}

It's now exiting properly, but the compiler says that a void function may not return a value. Did I do this correctly, having the exit() return 0?

[c0defisher]

you cannot obviously return a value in a void function as the compiler says , why dont you try to make it an integer return type function. what is your aim in this program exactly?

[Chervil]

Did you try the <cstdlib> exit function, rather than writing your own?
http://www.cplusplus.com/reference/cstdlib/exit/

[riechan]

@c0defisher: That's actually just a part of the whole program. Basically, what happens is, when the user selects the 4th option, the application closes.

@Chervil: I'll try looking into that, thanks. If ever, this will be the first time that I'll be using that library.

[riechan]

Thanks guys, the exit() from cstdlib fixed the warning message. Sorry for the rather basic question, I'm still brushing up on my programming! :)

[Chervil]

Looking at the logic of the program, the while loop will terminate when opt == 4, so there may not be any need to do anything, other than output the message.

    while (opt!=4)
    {
        opt = menu();
        switch(opt)
        {
            case 4:
                clrscr();
                printf("Exiting application...");
                getch();
                break;
                
            case 5:
               // etc.
               
            
        }
    }

When the break is executed at line 10, that ends the switch block. Then the while condition (opt!=4) is tested. Since it is no longer true, the loop terminates and the program will then exit normally.
Thus, there is no need to use any sort of exit function here.

[riechan]

I hadn't realized that until you pointed that out. Thanks!