How to stop C++ console application from exiting immediately?

Question

Hello everybody. Lately, I've been trying to learn C++ from this website. Unfortunately whenever I try to run one of the code samples, I see that program open for about a half second and then immediately close. Is there any way to stop the program from closing immediately so that I can see the fruits of my effort? Thanks in advance.

Answer 1

Edit: As Charles Bailey rightly points out in a comment below, this won't work if there are characters buffered in stdin, and there's really no good way to work around that. If you're running with a debugger attached, John Dibling's suggested solution is probably the cleanest solution to your problem.

That said, I'll leave this here and maybe someone else will find it useful. I've used it a lot as a quick hack of sorts when writing tests during development.

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At the end of your main function, you can call:

std::getchar();

This will get a single character from stdin, thus giving you the "press any key to continue" sort of behavior (if you actually want a "press any key" message, you'll have to print one yourself).

You need to #include <cstdio> for getchar.

Answer 2

The solution by James works for all Platforms.

Alternatively on Windows you can also add the following just before you return from main function:

  system("pause");

This will run the pause command which waits till you press a key and also displays a nice message Press any key to continue . . .

Answer 3

Why not just run the program from a console ie run the program from cmd.exe if you're using Windows. That way the window stays open after the program finishes.

[EDIT]: When I use KDevelop4 there is a fully fledged instance of Bash (a Linux CLI) running in a tab at the bottom of the IDE. Which is what I use in these sort of circumstances.

Answer 4

See if your IDE has a checkbox in project setting to keep the window open after the program terminates. If not, use std::cin.get(); to read a character at the end of main function. However, be sure to use only line-based input (std::getline) or to deal with leftover unread characters otherwise (std::ignore until newline) because otherwise the .get() at the end will only read the garbage you left unread earlier.

Answer 5

If you run your code from a competent IDE, such as Code::Blocks, the IDE will manage the console it uses to run the code, keeping it open when the application closes. You don't want to add special code to keep the console open, because this will prevent it functioning correctly when you use it for real, outside of the IDE.

Answer 6

If you are using Visual Studio and you are starting the console application out of the IDE:

pressing CTRL-F5 (start without debugging) will start the application and keep the console window open until you press any key.

Answer 7

If you are actually debugging your application in Visual C++, press F5 or the green triangle on the toolbar. If you aren't really debugging it (you have no breakpoints set), press Ctrl+F5 or choose Start Without Debugging on the menus (it's usually on the Debug menu, which I agree is confusing.) It will be a little faster, and more importantly to you, will pause at the end without you having to change your code.

Alternatively, open a command prompt, navigate to the folder where your exe is, and run it by typing its name. That way when it's finished running the command prompt doesn't close and you can see the output. I prefer both of these methods to adding code that stops the app just as its finished.

Answer 8

Okay I'm guessing you are on Windows using Visual Studio... why? Well because if you are on some sort of Linux OS then you'd probably be running it from the console.

Anyways, you can add crap to the end of your program like others are suggesting, or you can just hit CTRL + F5 (start without debugging) and Visual Studio will leave the console up once complete.

Another option if you want to run the Debug version and not add crap to your code is to open the console window (Start -> Run -> cmd) and navigate to your Debug output directory. Then, just enter the name of your executable and it will run your debug program in the console. You can then use Visual Studio's attach to process or something if you really want to.

Answer 9

I usually just put a breakpoint on main()'s closing curly brace. When the end of the program is reached by whatever means the breakpoint will hit and you can ALT-Tab to the console window to view the output.

Answer 10

Add the following lines before any exit() function or before any returns in main():

std::cout << "Paused, press ENTER to continue." << std::endl;
cin.ignore(1000000);

Answer 11

you could also stick

while(true)
    ;

or

for(;;)
    ;

at the end

Answer 12

you can even declare an integer at the beginning of your main() function (say int a;) and put std::cin >> a; just before the return value. So the program will keep running until you press a key and enter.