Fix option code so that -? is handled correctly.

diff --git a/cmd/tools/cvtgxl.c b/cmd/tools/cvtgxl.c
index 592a6089cb7b9153055e9d6491bf9de67bc4eb26..26591169283dd2fa2d51da098da560f9118920fd 100644 (file)
--- a/cmd/tools/cvtgxl.c
+++ b/cmd/tools/cvtgxl.c
@@ -147,7 +147,7 @@ static void initargs(int argc, char **argv)
     int c;
 
     CmdName = cmdName(argv[0]);
-    while ((c = getopt(argc, argv, ":gdo:")) != -1) {
+    while ((c = getopt(argc, argv, ":gdo:?")) != -1) {
        switch (c) {
        case 'd':
            act = ToDot;