aboutsummaryrefslogtreecommitdiffstats
path: root/csci4061/110920_breakout/chap8
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--csci4061/110920_breakout/chap8/Makefile12
-rw-r--r--csci4061/110920_breakout/chap8/pgm_8_1.c42
-rw-r--r--csci4061/110920_breakout/chap8/pgm_8_5.c43
3 files changed, 97 insertions, 0 deletions
diff --git a/csci4061/110920_breakout/chap8/Makefile b/csci4061/110920_breakout/chap8/Makefile
new file mode 100644
index 0000000..bd92bec
--- /dev/null
+++ b/csci4061/110920_breakout/chap8/Makefile
@@ -0,0 +1,12 @@
+pgm81: pgm_8_1.c
+ gcc pgm_8_1.c -lm -o out
+ ./out 5
+
+pgm85: pgm_8_5.c
+ gcc pgm_8_5.c -lm -o out
+ ./out
+
+.PHONY: clean
+
+clean:
+ rm out
diff --git a/csci4061/110920_breakout/chap8/pgm_8_1.c b/csci4061/110920_breakout/chap8/pgm_8_1.c
new file mode 100644
index 0000000..a979bb6
--- /dev/null
+++ b/csci4061/110920_breakout/chap8/pgm_8_1.c
@@ -0,0 +1,42 @@
+// Program 8.1
+
+#include <math.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+int main(int argc, char *argv[]) {
+ int i;
+ sigset_t intmask;
+ int repeatfactor;
+ double y = 0.0;
+
+ if (argc != 2) {
+ fprintf(stderr, "Usage: %s repeatfactor\n", argv[0]);
+ return 1;
+ }
+ repeatfactor = atoi(argv[1]);
+ if ((sigemptyset(&intmask) == -1) || (sigaddset(&intmask, SIGINT) == -1)){
+ perror("Failed to initialize the signal mask");
+ return 1;
+ }
+ for ( ; ; ) {
+ if (sigprocmask(SIG_BLOCK, &intmask, NULL) == -1)
+ break;
+ fprintf(stderr, "SIGINT signal blocked\n");
+ for (i = 0; i < repeatfactor; i++)
+ y += sin((double)i);
+ fprintf(stderr, "Blocked calculation is finished, y = %f\n", y);
+ sleep(3);
+ if (sigprocmask(SIG_UNBLOCK, &intmask, NULL) == -1)
+ break;
+ fprintf(stderr, "SIGINT signal unblocked\n");
+ for (i = 0; i < repeatfactor; i++)
+ y += sin((double)i);
+ fprintf(stderr, "Unblocked calculation is finished, y=%f\n", y);
+ sleep(3);
+ }
+ perror("Failed to change signal mask");
+ return 1;
+} \ No newline at end of file
diff --git a/csci4061/110920_breakout/chap8/pgm_8_5.c b/csci4061/110920_breakout/chap8/pgm_8_5.c
new file mode 100644
index 0000000..b20cdfa
--- /dev/null
+++ b/csci4061/110920_breakout/chap8/pgm_8_5.c
@@ -0,0 +1,43 @@
+// Program 8.5
+
+#include <math.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+static volatile sig_atomic_t doneflag = 0;
+
+/* ARGSUSED */
+static void setdoneflag(int signo) {
+ doneflag = 1;
+}
+
+int main (void) {
+ struct sigaction act;
+ int count = 0;
+ double sum = 0;
+ double x;
+
+ act.sa_handler = setdoneflag; /* set up signal handler */
+ act.sa_flags = 0;
+ if ((sigemptyset(&act.sa_mask) == -1) ||
+ (sigaction(SIGINT, &act, NULL) == -1)) {
+ perror("Failed to set SIGINT handler");
+ return 1;
+ }
+
+ while (!doneflag) {
+ x = (rand() + 0.5)/(RAND_MAX + 1.0);
+ sum += sin(x);
+ count++;
+ printf("Count is %d and average is %f\n", count, sum/count);
+ sleep(3);
+ }
+
+ printf("Program terminating ...\n");
+ if (count == 0)
+ printf("No values calculated yet\n");
+ else
+ printf("Count is %d and average is %f\n", count, sum/count);
+ return 0;
+} \ No newline at end of file