| 1 | #include <stdio.h> |
| 2 | #include <stdlib.h> |
| 3 | #include <unistd.h> |
| 4 | |
| 5 | #include <signal.h> |
| 6 | #include <time.h> |
| 7 | |
| 8 | struct timespec *start_time, *stop_time; |
| 9 | int done; |
| 10 | |
| 11 | void handle_start() { |
| 12 | |
| 13 | if(clock_gettime(CLOCK_PROCESS_CPUTIME_ID, start_time) == -1) { |
| 14 | |
| 15 | printf("failed to get start time.\n"); |
| 16 | exit(1); |
| 17 | } |
| 18 | } |
| 19 | |
| 20 | void handle_stop() { |
| 21 | |
| 22 | long int start_sec, stop_sec, delta; |
| 23 | |
| 24 | if(clock_gettime(CLOCK_PROCESS_CPUTIME_ID, stop_time) == -1) { |
| 25 | |
| 26 | printf("failed to get stop time.\n"); |
| 27 | exit(1); |
| 28 | } |
| 29 | |
| 30 | start_sec = ((long int) start_time->tv_nsec); |
| 31 | stop_sec = ((long int) stop_time->tv_nsec); |
| 32 | |
| 33 | delta = stop_sec - start_sec; |
| 34 | |
| 35 | printf("%ld nanoseconds elapsed between signals.\n", delta); |
| 36 | |
| 37 | done = 1; |
| 38 | } |
| 39 | |
| 40 | int main(int argc, char *argv[]) { |
| 41 | |
| 42 | done = 0; |
| 43 | |
| 44 | start_time = (struct timespec *) calloc(1, sizeof(struct timespec)); |
| 45 | stop_time = (struct timespec *) calloc(1, sizeof(struct timespec)); |
| 46 | |
| 47 | if(signal(SIGTSTP, handle_start) == SIG_ERR || |
| 48 | signal(SIGCONT, handle_stop) == SIG_ERR) { |
| 49 | |
| 50 | printf("could not bind signal handlers\n"); |
| 51 | return 1; |
| 52 | } |
| 53 | |
| 54 | terminate_check: |
| 55 | |
| 56 | pause(); |
| 57 | |
| 58 | if(!done) |
| 59 | goto terminate_check; /* sorry */ |
| 60 | |
| 61 | free(start_time); |
| 62 | free(stop_time); |
| 63 | |
| 64 | return 0; |
| 65 | } |