Programming with POSIX® Threads

18 void *worker_routine (void *arg)

19 {

20  int counter;

21

22  for (counter = 0; ; counter++)

23  if ((counter % 1000) == 0)

24  pthread_testcancel ();

25  }

26

27 /*

28 * Cancellation cleanup handler for the contractor thread. It

29 * will cancel and detach each worker in the team.

30 */

31 void cleanup (void *arg)

32 {

33  team_t *team = (team_t *)arg;

34  int count, status;

35

36  for (count = team->join_i; count < THREADS; count++) {

37  status = pthread_cancel (team->workers[count]);

38  if (status != 0)

39  err_abort (status, "Cancel worker");

40

41  status = pthread_detach(team->workers[count]);

42  if (status != 0)

43  err_abort (status, "Detach worker");

44  printf ("Cleanup: canceled %d\n", count);

45  }

46 }

47

48 /*

49 * Thread start routine for the contractor. It creates a team of

50 * worker threads, and then joins with them. When canceled, the

51 * cleanup handler will cancel and detach the remaining threads.

52 */

53 void *thread_routine (void *arg)

54 {

53  team_t team; /* team info */

56  int count;

57  void *result; /* Return status */

58  int status;

59

60  for (count = 0; count < THREADS; count++) {

61  status = pthread_create (

62  &team.workers[count], NULL, worker_routine, NULL);

63  if (status != 0)

64  err_abort (status, "Create worker");

55  }

66  pthread_cleanup_push (cleanup, (void*)&team);

67

68  for (team.join_i = 0; team.join_i < THREADS; team.join_i++) {

69  status = pthread_join (team.workers[team.join_i], &result);

70  if (status != 0)

71  err_abort (status, "Join worker");

72  }

73

74  pthread_cleanup_pop (0);

75  return NULL;

76 }

77

78 int main (int argc, char *argv[])

79 {

80  pthread_t thread_id;

81  int status;

82

83 #ifdef sun

84 /*

85 * On Solaris 2.5, threads are not timesliced. To ensure

86 * that our threads can run concurrently, we need to

87 * increase the concurrency level to at least 2 plus THREADS

88 * (the number of workers).

89 */

90  DPRINTF (("Setting concurrency level to %d\n", THREADS+2));

91  thr_setconcurrency (THREADS+2);

92 #endif

93  status = pthread_create (&thread_id, NULL, thread_routine, NULL);

94  if (status != 0)

95  err_abort (status, "Create team");

96  sleep (5);

97  printf ("Cancelling...\n");

98  status = pthread_cancel (thread_id);

99  if (status != 0)

100  err_abort (status, "Cancel team");

101 status = pthread_join (thread_id, NULL);

102 if (status != 0)

103 err_abort (status, "Join team");

104 }

5.4 Thread-specific data