From 7521e30b527409a49b129e344b20a87b7d5edf2b Mon Sep 17 00:00:00 2001
From: Scott Worley <scottworley@scottworley.com>
Date: Wed, 13 Sep 2023 15:16:27 -0700
Subject: [PATCH 1/1] Show usage message on invalid command line argument

---
 tl-append.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/tl-append.c b/tl-append.c
index 4edd58a..a3e9a4e 100644
--- 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;
-- 
2.44.1