util dic: print usage

1 files changed, 15 insertions, 5 deletions

diff --git a/util/bin/dic b/util/bin/dic
index aceee6e6..b3dac847 100755
--- a/util/bin/dic
+++ b/util/bin/dic
@@ -4,12 +4,18 @@
 # multiple WORDs may be seperated by + like this: multiple+words
 set -euf
 
-# all three are used by GET
-search="$1"
-langlang="${2-en}de"
-lang="de"
-
 main() {
+
+  case $# in
+    1|2) :;; # ok
+    *) usage; exit 23;;
+  esac
+
+  # all three are used by GET
+  search="$1"
+  langlang="${2-en}de"
+  lang="de"
+
   GET | simplify | tac
 }
 
@@ -65,4 +71,8 @@ simplify() {
   '
 }
 
+usage() {
+  sed -rn '/^# usage:/,/^[^#]/{/^#/{s/# //;p}}' "$0" >&2
+}
+
 main "$@"