Синтаксис для изменения режима связывания интерфейса

Не sed, в основном bash:

string=$(cat <<'END'
succ_1st=`grep 'resulted in successful answer' $path_tmp/named.stats.tmp | sed '/localhost.localdomain/,/testdns.net/{//!d}' | awk '{ print $1 }' | grep -m1 ''`
END
)

var=$(cut -d'`' -f1 <<<"$string")
code=$(cut -d'`' -f2 <<<"$string")
IFS='|' read -ra commands <<<"$code"
filename=$( set -f; eval set -- "${commands[0]}"; echo ${!#} )  # danger
tmp=${commands[0]//${filename//\//\\\/}/}
commands[0]="${commands[1]} $filename"
commands[1]=$tmp
printf -v new '%s`%s`' "$var" "$(IFS='|'; echo "${commands[*]}")"
echo "$new"

succ_1st=` sed '/localhost.localdomain/,/testdns.net/{//!d}'  $path_tmp/named.stats.tmp|grep 'resulted in successful answer'  | awk '{ print $1 }' | grep -m1 ''`