graphics/fontforge: Update the pre-install catcher.

Signed-off-by: Dave Woodfall <dave@slackbuilds.org>

Signed-off-by: Andrew Clemons <andrew.clemons@gmail.com>

graphics/fontforge/fontforge.SlackBuild

@@ -44,9 +44,14 @@ FREETYPE=${FREETYPE:-2.11.1}
 GNULIB=${GNULIB:-0.1}
 UTHASH=${UTHASH:-2.3.0}
 
-if [ -f "$( echo /var/lib/pkgtools/packages/$PRGNAM-*-*-* )" ]; then
-  echo "Please uninstall any previous versions of $PRGNAM first."
-  echo "Exiting."
+# This ought to be more reliable than testing if a package DB file
+# exists.  A little convoluted perhaps.
+if $PRGNAM -v 2>/dev/null |
+     sed -n "s,^\($PRGNAM .*\),Found existing installation:\n \n\1,p
+     n;p;a\ " | grep -v "^$"; then
+
+  echo "Please uninstall any previous versions of $PRGNAM before building
+a new one."
   exit 1
 fi