/usr/lib/xen-common/bin/xen-toolstack is in xen-utils-common 4.9.2-0ubuntu1.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42  | #!/bin/sh -e
configfile=/etc/default/xen
dir=$(. /usr/lib/xen-common/bin/xen-dir); ret=$?; [ $ret -eq 0 ] || exit $ret
check() {
    local PATH
    if [ "$1" = xm ] || [ "$1" = xl ]; then
        PATH="$dir/bin"
    else
        PATH="$dir/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
    fi
    command -v "$1" || :
}
if [ -e $configfile ]; then
    . $configfile || true
fi
if [ "$TOOLSTACK" ]; then
    cmd=$(check "$TOOLSTACK")
    if [ "$cmd" ]; then
        echo "$cmd"
    else
        echo "WARING:  Can't find toolstack $TOOLSTACK, fallback to default!" >&2
        TOOLSTACK=
    fi
fi
if [ -z "$TOOLSTACK" ]; then
    cmd_xm=$(check xm)
    cmd_xl=$(check xl)
    if [ "$cmd_xm" ]; then
        echo "$cmd_xm"
    elif [ "$cmd_xl" ]; then
        echo "$cmd_xl"
    else
        echo "ERROR:  Toolstack not specifed and nothing detected, bailing out!" >&2
        exit 127
    fi
fi
 |