initial import

from
http://www.informit.com/store/programming-with-posix-threads-9780201633924

cancel_disable.c

@@ -0,0 +1,68 @@
+/*
+ * cancel_disable.c
+ *
+ * Demonstrate running a section of code with cancellation
+ * disabled.
+ */
+#include <pthread.h>
+#include "errors.h"
+
+static int counter;
+
+/*
+ * Thread start routine.
+ */
+void *thread_routine (void *arg)
+{
+    int state;
+    int status;
+
+    for (counter = 0; ; counter++) {
+
+        /*
+         * Each 755 iterations, disable cancellation and sleep
+         * for one second.
+         *
+         * Each 1000 iterations, test for a pending cancel by
+         * calling pthread_testcancel().
+         */
+        if ((counter % 755) == 0) {
+            status = pthread_setcancelstate (
+                PTHREAD_CANCEL_DISABLE, &state);
+            if (status != 0)
+                err_abort (status, "Disable cancel");
+            sleep (1);
+            status = pthread_setcancelstate (
+                state, &state);
+            if (status != 0)
+                err_abort (status, "Restore cancel");
+        } else
+            if ((counter % 1000) == 0)
+                pthread_testcancel ();
+    }
+}
+
+int main (int argc, char *argv[])
+{
+    pthread_t thread_id;
+    void *result;
+    int status;
+
+    status = pthread_create (
+        &thread_id, NULL, thread_routine, NULL);
+    if (status != 0)
+        err_abort (status, "Create thread");
+    sleep (2);
+    status = pthread_cancel (thread_id);
+    if (status != 0)
+        err_abort (status, "Cancel thread");
+
+    status = pthread_join (thread_id, &result);
+    if (status != 0)
+        err_abort (status, "Join thread");
+    if (result == PTHREAD_CANCELED)
+        printf ("Thread cancelled at iteration %d\n", counter);
+    else
+        printf ("Thread was not cancelled\n");
+    return 0;
+}