debug_info "killing all dead sessions"
        (
        while read -u 5 i ; do
            mac="${i%% *}" # first word
            session="${i##* }" # last word
            server=$(clientmac2server "$mac")
            debug_info "killing session $session on $server"
            ssh -t $server sudo /opt/SUNWut/lib/utdtsession -t "$i" delete || break
        done
        ) 5< <(lsdead)
        # BAM!! re06huxa says: this loop is nice
        # ( ) spawns a subshell
        # 5< FILE redirects the input of FILE to fd 5
        # <(COMMAND) redirects the stdout of COMMAND and simulats like a file
        # i.e. `COMMAND` is the same as `cat <(COMMAND)`