flush stdin

[dezz101]

Hey, now i know your not sposed to flush(stdin) nstuff, but can someone give me an alternative please. I have used fscanf to read many doubles to a dynamic memory allocated pointer. I have then called the function in main and now the program is complete. all i want is for the program to pause before it exits so I chucked in a getchar(); at the end but obviously it skips it because of the return carriage in stdin or whatever happens there.

Is there something simple to do to get rid of this problem

Thanx guys

[dezz101]

any1???

[laserlight]

Read the FAQ: How do I get my program to wait for a keypress?

[george_1988]

Does using getch(); work any better?

Also, can someone illustrate the reasons why fflush(stdin) should not be used?

I'm not an expert or anything but I don't see what's wrong with it. When I use fgets or if I have characters like newlines and stuff in the input stream fflush(stdin) almost always solves the problem.

[tabstop]

The main reason not to use it is that it doesn't exist. fflush only works on output streams (or at least that's what the standard says; your compiler may decide to not cause an error, but that's neither here nor there).

The same thing is true of getch(); it does not exist in standard C.

[cpjust]

fflush(stdin) almost always solves the problem.

I think you just answered your own question.

[Elysia]

The standard does not say that fflush(stdin) is defined, and therefore it is undefined. It may work, it may not work. And for some time you may find that it works, but then suddenly you find that it doesn't work. Because it's undefined.
The story on getch is that it is non-standard (it's an extension not supported by all compilers). Instead, you should use getchar() or get a better IDE that allows you to run the app w/o closing it or get a debugger that allows you to put a breakpoint at the end of main so the window doesn't close or run the darn thing from the command line.

[cpjust]

The story on getch is that it is non-standard (it's an extension not supported by all compilers). Instead, you should use getchar() or get a better IDE that allows you to run the app w/o closing it or get a debugger that allows you to put a breakpoint at the end of main so the window doesn't close or run the darn thing from the command line.

That's not the only reason people use getch() or getchar() though. Actually, I've never used it at the end of my programs, since I always use VC++. I like getch() or getche() because I can create a simple interactive console-based menu without having to press enter after a key.