I have this code snippet and I even reading about the signal system call a few times, I still do not understand why the program stops the fourth time I press CTRL-C, and not the third. Thanks in advance!
#include <stdio.h>
#include <signal.h>
#include <unistd.h>
int i=0;
void handler(int sig)
{
i++;
printf("CTRL-C\n");
if (i==3)
signal(SIGINT, SIG_DFL);
}
int main()
{
signal(SIGINT,handler);
while (1)
{
printf("Hello world!\n");
sleep(1);
}
return 0;
}
I read that the signal system call is not portable, so it may help if I mention I am using the last version of Ubuntu (14.04).
Your custom handler gets called three times. The third time, it registers a new signal handler (namely the default one), which terminates the program the next time the signal is delivered.
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