1. Ctrl-c
2. Ctrl-z
3. fg/bg
4. Ctrl-\

1. SIGKILL
2. 14
3. SIGALRM
4. SIGABRT
5. 21
6. 1
7. SIGCHLD
8. SIGTTOU

1. killall -17 sleep
2. kill -9 2237
3. killall -SIGUSR1 a.out
4. kill -SIGABRT -1
5. killall sleep
6. killall -u

On a lab machine, run the following program in the background

~aviv/ic221-hw/hw09/ic221-signaler &

From the same (or another) terminal on the same machine, send the program the following two signals below and describe the results.

1. (3 points) SIGUSR1
2. (3 points) SIGUSR2

Consider the program below and answer the associated questions:

int count = 0;

void handler(int signum){

  printf("You Shot Me!\n");
  count++;

  if(count > 3){
    printf("I'm dead!\n");
    exit(1);
  }

}

int main(){

  //establish signal hander for SIGTINT and SIGSTOP
  signal(SIGTINT,handler);
  signal(SIGTSTP,handler);

  //loop forever
  while(1);

}

1. (3 points) What is the output of the program if the user hits Ctrl-c only once? Explain.
2. (3 points) What is the output of the program if the user hits Ctrl-c four times? Explain.
3. (3 points) What is the output of the program if the user hits Ctrl-c three times and Ctrl-Z once? Explain.

(10 points) How many times doe the program below print alarm? Explain

int count = 10;

void handler(int sugnum){

  printf("Alarm!\n");
  count /= 2;
  alarm(count);

}

int main(){

  signal(SIGALRM, handler);
  alarm(count);

  while(1) pause();
}

(10 points) Convert the following use of signal() below to a sigaction() call.

signal(SIGUSR1, handler);