How to interrupt a C++ program

Question

This is the gist the program :

while(true)
{
//bunch of codes that gets data from port ,
//if there is no data it waits here .

}

i am using linux , is there any inbuilt support for keypresses like Ctrl+C . I can catch that using signal(SIGINT, signal_callback_handler); but Ctrl+C has some problem as it gives errors .

i want to get out of this loop on keypress , is this possible ? If yes , how to do it .

`break` well get you out the loop. to get the key, you well probably need a thread. — elyashiv, Oct 20 '12 at 17:53
Which OS? On Windows, checking with `GetAsyncKeyState` would humbly suffice for a specific key. — chris, Oct 20 '12 at 17:54
"if there is no data it waits here" I think you mean *spins* here, unless your port-read is blocking. — WhozCraig, Oct 20 '12 at 17:55
i am using linux , is there any inbuilt support for keypresses like Ctrl+C . I can catch that using **signal(SIGINT, signal_callback_handler);** but Ctrl+C has some problem it gives errors . — rajat, Oct 20 '12 at 17:57
On Linux, you can use NCurses. This has been answered already: http://stackoverflow.com/a/4028974/856199 — Nikos C., Oct 20 '12 at 18:18
@rajat Remember than when you use ncurses in your program, you have to link the ncurses library when you build it. Simply add `-lncurses` at the end of your g++ command line. — Nikos C., Oct 20 '12 at 18:33

score 0 · Answer 1 · answered Oct 20 '12 at 17:56

0

while(!_kbhit()){
    // do stuff here.
}

Works on Windows.

answered Oct 20 '12 at 17:56

CodeAngry

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score 0 · Accepted Answer · answered Oct 20 '12 at 18:02

0

You can signal an interupt

      #include <csignal>

      raise(SIGINT);

or

     raise(SIGABRT);

answered Oct 20 '12 at 18:02

Rahul Tripathi

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which signal it will catch , Ctrl+C ? Any-others ? – rajat Oct 20 '12 at 18:09
Ctrl+C..I would suggest you to refer this link for signal handling:- http://www.delorie.com/gnu/docs/gdb/gdb_39.html Hope it works!!1 – Rahul Tripathi Oct 20 '12 at 18:11

score 0 · Answer 3 · edited May 23 '17 at 12:33

The function that can terminate your program is exit().

To input a premature termination of your cicle you can use break.

If you are willing to use some C oriented solution i suggest to take a look at this question.

For something strictly related to linux you probably should refer to the ncurses library in combination with the exit function.

Also do not assume that a particular key combination is equal to a termination, many terminals are not real terminals but emulators, and many emulators are customizable, by the OS creator and by the user.

How to interrupt a C++ program

3 Answers3