#!/bin/sh
[ $# -eq 0 ] && { echo "usage: mp [-vol] [mplayer_opts] file ..." >&2; exit 1; }
case "$1" in
-[0-9]*)
    tmp=$(echo $1 | sed 's/^-//'); vol="-af volume=$tmp"; shift;;
esac
mplayer -really-quiet $vol -fs "$@"
.