Issue#1: a command option has been added.

src/exifdate.c

@@ -37,8 +37,9 @@
 #endif
 
 typedef enum {
-  EDT_MODIFY = 0,
+  EDT_MODIFY_FO = 0,
   EDT_DISPLAY = 1,
+  EDT_MODIFY_ED = 2,
 } edt_mode_t;
 
 static void display_help(FILE *o, const char *exec_name)
@@ -52,6 +53,8 @@ static void display_help(FILE *o, const char *exec_name)
   fprintf(o, "\nOptions:\n");
   fprintf(o, "\t%-36s Display date and time from exif data only, don't update file creation date.\n",
           "-d | --display-date");
+  fprintf(o, "\t%-36s Fix/create EXIF creation date based on the file creation date.\n",
+          "-e | --exif-date-fix");
   fprintf(o, "\t%-36s Display help.\n", "-h | --help");
   fprintf(o, "\t%-36s Display version information.\n\n", "-v | --version");
 
@@ -113,7 +116,7 @@ static time_t exifdt_tm(const char *dtbuf)
 int main(int argc, char **argv)
 {
   int opt, fargs = 0, i = 0;
-  edt_mode_t mode = EDT_MODIFY;
+  edt_mode_t mode = EDT_MODIFY_FO;
   char **fn_name = NULL;
   ExifData *ef;
   ExifEntry *entry;
@@ -126,18 +129,22 @@ int main(int argc, char **argv)
     static struct option long_options[] =
     {
       {"display-date", no_argument, NULL, 'd'},
+      {"exif-date-fix", no_argument, NULL, 'e'},
       {"help", no_argument, NULL, 'h'},
       {"version", no_argument, NULL, 'v'},
       {NULL, 0, NULL, 0},
     };
 
-    if((opt = getopt_long(argc, argv, "dhv", long_options, &option_index)) == -1)
+    if((opt = getopt_long(argc, argv, "dehv", long_options, &option_index)) == -1)
       break;
 
     switch(opt) {
       case 'd':
         mode = EDT_DISPLAY;
         break;
+      case 'e':
+        mode = EDT_MODIFY_ED;
+        break;
       case 'h':
         display_help(stdout, argv[0]);
         return 0;
@@ -189,7 +196,7 @@ int main(int argc, char **argv)
             case EDT_DISPLAY:
               fprintf(stdout, "%s date and time: %s\n",fn_name[i], dtbuf);
               break;
-            case EDT_MODIFY:
+            case EDT_MODIFY_FO:
               /* convert exif format to timeval */
               exif_dt = exifdt_tm(dtbuf);
               if(exif_dt == (time_t) -1)
@@ -200,6 +207,8 @@ int main(int argc, char **argv)
                 utime(fn_name[i], &ntimes);
               }
               break;
+            case EDT_MODIFY_ED:
+              break;
           }
         } else fprintf(stdout, "%s: No date and time information exists in exif.\n",
                        fn_name[i]);