globbing constant expressions use more idiomatic underscore rather than star;
precised
#!/usr/bin/env bash
#
# Author: Makarius
#
# DESCRIPTION: Proof General / Emacs interface wrapper
## diagnostics
function fail()
{
echo "$1" >&2
exit 2
}
## main
[ -z "$PROOFGENERAL_HOME" ] && fail "Missing Proof General installation (PROOFGENERAL_HOME)"
INTERFACE="$PROOFGENERAL_HOME/isar/interface"
[ ! -x "$INTERFACE" ] && fail "Bad interface script: \"$INTERFACE\""
#legacy settings
export ISABELLE="$ISABELLE_PROCESS"
export ISATOOL="$ISABELLE_TOOL"
exec "$INTERFACE" "$@"