linux 2.6.16.38 w/ vs2.0.3-rc1

[linux-2.6.git] / Documentation / watchdog / pcwd-watchdog.txt

diff --git a/Documentation/watchdog/pcwd-watchdog.txt b/Documentation/watchdog/pcwd-watchdog.txt
index d9ee633..12187a3 100644 (file)
--- a/Documentation/watchdog/pcwd-watchdog.txt
+++ b/Documentation/watchdog/pcwd-watchdog.txt
@@ -22,9 +22,78 @@
  to run the program with an "&" to run it in the background!)
 
  If you want to write a program to be compatible with the PC Watchdog
- driver, simply use of modify the watchdog test program:
- Documentation/watchdog/src/watchdog-test.c
-
+ driver, simply do the following:
+
+-- Snippet of code --
+/*
+ * Watchdog Driver Test Program
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <linux/types.h>
+#include <linux/watchdog.h>
+
+int fd;
+
+/*
+ * This function simply sends an IOCTL to the driver, which in turn ticks
+ * the PC Watchdog card to reset its internal timer so it doesn't trigger
+ * a computer reset.
+ */
+void keep_alive(void)
+{
+    int dummy;
+
+    ioctl(fd, WDIOC_KEEPALIVE, &dummy);
+}
+
+/*
+ * The main program.  Run the program with "-d" to disable the card,
+ * or "-e" to enable the card.
+ */
+int main(int argc, char *argv[])
+{
+    fd = open("/dev/watchdog", O_WRONLY);
+
+    if (fd == -1) {
+       fprintf(stderr, "Watchdog device not enabled.\n");
+       fflush(stderr);
+       exit(-1);
+    }
+
+    if (argc > 1) {
+       if (!strncasecmp(argv[1], "-d", 2)) {
+           ioctl(fd, WDIOC_SETOPTIONS, WDIOS_DISABLECARD);
+           fprintf(stderr, "Watchdog card disabled.\n");
+           fflush(stderr);
+           exit(0);
+       } else if (!strncasecmp(argv[1], "-e", 2)) {
+           ioctl(fd, WDIOC_SETOPTIONS, WDIOS_ENABLECARD);
+           fprintf(stderr, "Watchdog card enabled.\n");
+           fflush(stderr);
+           exit(0);
+       } else {
+           fprintf(stderr, "-d to disable, -e to enable.\n");
+           fprintf(stderr, "run by itself to tick the card.\n");
+           fflush(stderr);
+           exit(0);
+       }
+    } else {
+       fprintf(stderr, "Watchdog Ticking Away!\n");
+       fflush(stderr);
+    }
+
+    while(1) {
+       keep_alive();
+       sleep(1);
+    }
+}
+-- End snippet --
 
  Other IOCTL functions include: