udevadm,..: make --help output of udev tools more like the output of the various...

[elogind.git] / src / udev / v4l_id / v4l_id.c

diff --git a/src/udev/v4l_id/v4l_id.c b/src/udev/v4l_id/v4l_id.c
index 8dcb645ed9f1b7d3c3b81334a2e4c943f7a761e2..0ebe43463992208ef1b28774c02d06e58c5487ab 100644 (file)
--- a/src/udev/v4l_id/v4l_id.c
+++ b/src/udev/v4l_id/v4l_id.c
@@ -18,11 +18,7 @@
 #include <string.h>
 #include <ctype.h>
 #include <stdlib.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
 #include <unistd.h>
-#include <errno.h>
 #include <fcntl.h>
 #include <getopt.h>
 #include <sys/types.h>
@@ -30,17 +26,18 @@
 #include <sys/ioctl.h>
 #include <linux/videodev2.h>
 
-int main (int argc, char *argv[])
-{
+#include "util.h"
+
+int main(int argc, char *argv[]) {
         static const struct option options[] = {
                 { "help", no_argument, NULL, 'h' },
                 {}
         };
-        int fd;
+        _cleanup_close_ int fd = -1;
         char *device;
         struct v4l2_capability v2cap;
 
-        while (1) {
+        for (;;) {
                 int option;
 
                 option = getopt_long(argc, argv, "h", options, NULL);
@@ -49,7 +46,10 @@ int main (int argc, char *argv[])
 
                 switch (option) {
                 case 'h':
-                        printf("Usage: v4l_id [--help] <device file>\n\n");
+                        printf("%s [-h,--help] <device file>\n\n"
+                               "Video4Linux device identification.\n\n"
+                               "  -h  Print this message\n"
+                               , program_invocation_short_name);
                         return 0;
                 default:
                         return 1;
@@ -59,11 +59,11 @@ int main (int argc, char *argv[])
 
         if (device == NULL)
                 return 2;
-        fd = open (device, O_RDONLY);
+        fd = open(device, O_RDONLY);
         if (fd < 0)
                 return 3;
 
-        if (ioctl (fd, VIDIOC_QUERYCAP, &v2cap) == 0) {
+        if (ioctl(fd, VIDIOC_QUERYCAP, &v2cap) == 0) {
                 printf("ID_V4L_VERSION=2\n");
                 printf("ID_V4L_PRODUCT=%s\n", v2cap.card);
                 printf("ID_V4L_CAPABILITIES=:");
@@ -82,6 +82,5 @@ int main (int argc, char *argv[])
                 printf("\n");
         }
 
-        close (fd);
         return 0;
 }