lib/Tools/display

avoid jdk-11.0.6+10: it shows problem "S8217731: Font rendering and glyph spacing changed from jdk-8 to jdk-11" https://bugs.openjdk.java.net/browse/JDK-8217731 even though the changelog claims to have resolved this;

#!/usr/bin/env bash
#
# Author: Makarius
#
# DESCRIPTION: display document (in DVI or PDF format)


PRG="$(basename "$0")"

function usage()
{
  echo
  echo "Usage: isabelle $PRG DOCUMENT"
  echo
  echo "  Display DOCUMENT (in DVI or PDF format)."
  echo
  exit 1
}

function fail()
{
  echo "$1" >&2
  exit 2
}


## main

[ "$#" -ne 1 -o "$1" = "-?" ] && usage

DOCUMENT="$1"; shift

[ -f "$DOCUMENT" ] || fail "Bad document: \"$DOCUMENT\""

case "$DOCUMENT" in
  *.dvi)
    exec "$DVI_VIEWER" "$DOCUMENT"
    ;;
  *.pdf)
    exec "$PDF_VIEWER" "$DOCUMENT"
    ;;
  *)
    fail "Unknown document type: \"$DOCUMENT\"";
esac