Index: texmf-dist/scripts/installfont/installfont-tl
--- texmf-dist/scripts/installfont/installfont-tl.orig
+++ texmf-dist/scripts/installfont/installfont-tl
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/bin/ksh
 #
 # installfont-tl [options]
 #
@@ -93,7 +93,7 @@ then
   echo -e "`basename $0`: Could not find command line arguments.\nUse the '--help' option for explanation."
   echo -e "Continue with default script variables? (y/n)"
   read ANSWER
-  if [ $ANSWER = "n" -o $ANSWER = "N" ]
+  if [ X"$ANSWER" = "Xn" -o X"$ANSWER" = "XN" ]
   then
     exit 1
   fi
