__prompt_exit()
 {
   if [ "$3" -eq 0 ]
   then
     return 0
   elif [ "$3" -lt 128 ]
   then
     printf "$1" "$3"
   else
     __prompt_exit_signal="$(kill -l "$(($3 - 128))" 2> '/dev/null')"
     if ! [ "$__prompt_exit_signal" ]
     then
       printf "$1" "$3"
       return 0
     fi
     for __prompt_exit_signal_mask in $2
     do
       if [ "$__prompt_exit_signal" = "$__prompt_exit_signal_mask" ]
       then
         return 0
       fi
     done
     printf "$1" "$__prompt_exit_signal"
   fi
 }