Commit 46cba868 for libheif

commit 46cba868814164c8f5c335c508f9c587e2d11231
Author: Dirk Farin <dirk.farin@gmail.com>
Date:   Tue Sep 29 23:21:00 2026 +0200

    heif-enc: exit with an error when an option is unknown

    getopt_long() reports an unknown option, or an option without its argument,
    with the return value '?'. heif-enc did not handle it and went on, so a
    mistyped option was ignored and the image was encoded with the default value.

diff --git a/examples/heif_enc.cc b/examples/heif_enc.cc
index c8a51ca0..5f3bfec9 100644
--- a/examples/heif_enc.cc
+++ b/examples/heif_enc.cc
@@ -1906,6 +1906,11 @@ int main(int argc, char** argv)
       case OPTION_RAW_ENDIAN:
         raw_input_params.big_endian = (std::string(optarg) == "big");
         break;
+      case '?':
+        // An unknown option, or an option without its argument. getopt_long() has
+        // printed which one it is.
+        std::cerr << "Use '" << argv[0] << " --help' for the list of options.\n";
+        return 5;
     }
   }