diff --git a/examples/main.c b/examples/main.c
index c1e5143..bb756a7 100644
--- a/examples/main.c
+++ b/examples/main.c
@@ -24,21 +24,64 @@ get_username()
     return "";
 }
 
+void usage() {
+    fprintf(stderr, "Simple utility to leave comment using unix_fs_driver\n");
+    fprintf(stderr, "usage: <tool-name> [-p path] [-r reply_id] [-d displayname] [-i input_file]");
+    fprintf(stderr, "-p path:\t path to comment storage \n");
+    fprintf(stderr, "-r reply_id:\t ID of comment you are replying to, 0 if yours is top-level\n");
+    fprintf(stderr, "-d displayname:\t Displayname to attach to comment\n");
+    fprintf(stderr, "-i input_file:\t File containing comment text(defaults to stdin)\n");
+}
+
 int
-main(int argc, const char *argv[])
+main(int argc, char *argv[])
 {
     const Driver *driver = &unix_fs_driver;
     char *path = ".";
 
     char *user_sid = get_username();
     char *user_displayname = user_sid;
+    char *text_filename = NULL;
     int reply_id = 0;
+    
+    int opt;
+    while ((opt = getopt(argc, argv, "p:d:r:i:")) != -1) {
+        switch (opt) {
+        case 'p':
+            path = optarg;
+            break;
+        case 'd':
+            user_displayname = optarg;
+            break;
+        case 'r':
+            reply_id = strtol(optarg, NULL, 10);
+            if (reply_id < 0) {
+                fprintf(stderr, "error: reply id can't be less than 0\n");
+                usage();
+                exit(EXIT_FAILURE);
+            }
+            break;
+        case 'i':
+            text_filename = optarg;
+            break;
+        default:
+            usage();
+            exit(EXIT_FAILURE);
+        }
+    }
 
     size_t cur_buf_size = 256;
     size_t idx = 0;
 
     char *text = malloc(cur_buf_size);
 
+    FILE *input_stream = (text_filename ? fopen(text_filename, "r") : stdin);
+    if (input_stream == NULL) {
+        fprintf(stderr, "error: cannot open input file\n");
+        perror("fopen");
+        exit(EXIT_FAILURE);
+    }
+
     int ch;
     while ((ch = getchar()) != EOF) {
         if (idx + 1 == cur_buf_size) {
diff --git a/src/drivers/unix_fs/unix_fs_driver.c b/src/drivers/unix_fs/unix_fs_driver.c
index 387b2d7..7d91b10 100644
--- a/src/drivers/unix_fs/unix_fs_driver.c
+++ b/src/drivers/unix_fs/unix_fs_driver.c
@@ -66,6 +66,8 @@ deserialize_header(int fd, CommentHeader *header)
     return 0;
 }
 
+/* TODO: validate driver_data_ptr */
+
 int
 unix_fs_driver_leave_comment(void *driver_data_ptr, CommentHeader *header, char *text)
 {
@@ -80,7 +82,7 @@ unix_fs_driver_leave_comment(void *driver_data_ptr, CommentHeader *header, char
     id_ctrl_file_path = header_file_path = text_file_path = NULL;
     id_ctrl_file = NULL;
 
-    header_fd = text_fd = -1;
+    header_fd = text_fd = id_ctrl_fd = -1;
 
     path = ((UnixFsDriverData*) driver_data_ptr)->path;
     if (!is_valid_directory(path)) {