Show usage message on invalid command line argument

diff --git a/tl-append.c b/tl-append.c
index 4edd58a80b271edca77f959173f9367cb1092d59..a3e9a4ecb75fa40306fdadd4862d42f11ea0c0fe 100644 (file)
--- a/tl-append.c
+++ b/tl-append.c
@@ -26,6 +26,10 @@ typedef struct {
   int flock_lock;
 } conf_t;
 
+void usage() {
+  die("usage: tl-append [-i] [--no-fnctl-lock] [--no-flock-lock]");
+}
+
 conf_t parse_command_line(int argc, char *argv[]) {
   conf_t conf;
   conf.interactive = 0;
@@ -35,10 +39,12 @@ conf_t parse_command_line(int argc, char *argv[]) {
   for (int i = 1; i < argc; i++) {
     if (strcmp(argv[i], "-i") == 0 && isatty(2))
       conf.interactive = 1;
-    if (strcmp(argv[i], "--no-fnctl-lock") == 0)
+    else if (strcmp(argv[i], "--no-fnctl-lock") == 0)
       conf.fcntl_lock = 0;
-    if (strcmp(argv[i], "--no-flock-lock") == 0)
+    else if (strcmp(argv[i], "--no-flock-lock") == 0)
       conf.flock_lock = 0;
+    else
+      usage();
   }
 
   return conf;