[WATCHDOG] Documentation/watchdog/src/watchdog-simple.c: improve this code

Make some improvements for Documentation/watchdog/src/watchdog-simple.c.

Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

1 files changed, 14 insertions, 4 deletions

diff --git a/Documentation/watchdog/src/watchdog-simple.c b/Documentation/watchdog/src/watchdog-simple.c
index 47801bc7e742..4cf72f3fa8e9 100644
--- a/Documentation/watchdog/src/watchdog-simple.c
+++ b/Documentation/watchdog/src/watchdog-simple.c
@@ -3,15 +3,25 @@
 #include <unistd.h>
 #include <fcntl.h>
 
-int main(int argc, const char *argv[]) {
+int main(void)
+{
         int fd = open("/dev/watchdog", O_WRONLY);
+        int ret = 0;
         if (fd == -1) {
                 perror("watchdog");
-                exit(1);
+                exit(EXIT_FAILURE);
         }
         while (1) {
-                write(fd, "\0", 1);
-                fsync(fd);
+                ret = write(fd, "\0", 1);
+                if (ret != 1) {
+                        ret = -1;
+                        break;
+                }
+                ret = fsync(fd);
+                if (ret)
+                        break;
                 sleep(10);
         }
+        close(fd);
+        return ret;
 }