Catch Ctrl-C in C

c signals
Feldor picture Feldor · Nov 18, 2010 · Viewed 189.3k times · Source

How does one catch Ctrl+C in C?

Answer

Dirk Eddelbuettel picture Dirk Eddelbuettel · Nov 18, 2010

With a signal handler.

Here is a simple example flipping a bool used in main():

#include <signal.h>

static volatile int keepRunning = 1;

void intHandler(int dummy) {
    keepRunning = 0;
}

// ...

int main(void) {

   signal(SIGINT, intHandler);

   while (keepRunning) { 
      // ...

Edit in June 2017: To whom it may concern, particularly those with an insatiable urge to edit this answer. Look, I wrote this answer seven years ago. Yes, language standards change. If you really must better the world, please add your new answer but leave mine as is. As the answer has my name on it, I'd prefer it to contain my words too. Thank you.

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