gred: a filter emphasizing the given pattern

gred

#!/bin/sh

set -e
NAME=gred

err() {
	echo "$@" >&2
	exit 1
}

my_tput() {
	tput "$@" || err "$NAME: failed \`tput $@'"
}

[ $# = 1 ] || err "usage: $NAME pattern"

RED=`my_tput setaf 1`
INV=`my_tput smso`
NORMAL=`my_tput sgr0`

sed -e "s/$1/$RED$INV&$NORMAL/g"