1. /* signal_base.c */

2. #include

3. #include

4. #include

5. #include

6.

7. void handler(int signum) //signal handler

8. { printf("Hello World! ");

9. exit(1); //exit after printing

10. }

11.

12. int main(int argc, char * argv[])

13. { signal(SIGALRM,handler); //register handler to handle SIGALRM

14. alarm(1); //Schedule a SIGALRM for 1 second

15. while(1) sleep(5); //waiting for signal to be delivered

16. return 0; //never reached

17. }

Signal Handling Programming Problems Program the solutions to the following problems by extending signal_base.c:

1. Change signal_base.c such that after the handler is invoked, an additional printf("Turing was right! ") occurs in main() before exiting. You will probably need to use a global variable and change the condition on the while loop. Furthermore, change signal_base.c such that every second, first Hello World! prints from the signal handler followed by Turing was right! in main(), over and over again indefinitely. The output should look like:

Hello World!

Turing was right!

Hello World!

Turing was Right!

2. Write a new program based on your signal_base.c that after exiting (via CTRL-C), will print out the total time the program was executing in seconds. To accomplish this task, you will need to register a second signal handler for the SIGINT signal, the signal that is delivered when CTRL-C is pressed. Conceptually, your program will request a SIGALRM signal to occur every second, tracking the number of alarms delivered, and when the program exits via CTRL-C, it will print how many alarms occurred, or the number of seconds it was executed. Name your programs YourLastName_YourFirstName_Lab02-1.c and YourLastName_YourFirstName_Lab02-2.c You must include a comment on the top of your program like the following: /* CMPS 3600 OS Lastname Firstname Lab 02 */ Create a Makefile for your program and a README file explaining the basics about your program. The submission of all your files including your report will be through the Blackboard. The report should include screenshots and a conclusion assessing the importance of the signals. Its better if you submit your report in a PDF.