cmb_test3.sh

#!/bin/sh
dpv(){ command dpv -k -b "$0" -p "$items\n" -t "$*" -a "\nCombinations:" \
    -l "$total: "; }
items=
for deck in 1 2; do
    for card in A 2 3 4 5 6 7 8 9 10 J Q K; do
        for suit in S H C D; do
            items="$items $card$suit$deck"
        done
    done
done
items="${items# }"
total=$( cmb -tk5 $items )
start=$( date +%s )
trap exit SIGINT
clear
cmb -k5 $items | dpv cmb
end=$( date +%s )
elapsed1=$(( $end - $start ))
seventh=$(( $total / 7 ))
export items
start=$( date +%s )
time echo \
    :$seventh \
    $(( $seventh + 1 )):$seventh \
    $(( $seventh * 2 + 1 )):$seventh \
    $(( $seventh * 3 + 1 )):$seventh \
    $(( $seventh * 4 + 1 )):$seventh \
    $(( $seventh * 5 + 1 )):$seventh \
    $(( $seventh * 6 + 1 )): \
    | xargs -P7 -n1 sh -c '
        start=${1%%:*} count=${1#*:}
        cmb -k5 ${start:+-i$start} ${count:+-c$count} $items
    ' sh | dpv "xargs -P7 cmb"
end=$( date +%s )
elapsed2=$(( $end - $start ))
echo
awk -v e1=$elapsed1 -v e2=$elapsed2 'BEGIN {
    printf "cmb: %us   xargs: %us   opt: %.2fx\n", e1, e2, e1 / (e2 || 1)
}'