kiss/contrib/kiss-help

#!/bin/sh -e
# Read KISS documentation

cd "$KISS_ROOT/usr/share/doc/kiss" 2>/dev/null || {
    printf 'Documentation is missing from /usr/share/doc/kiss\n'
    exit 1
}

! [ -f "${1:-.}/index.txt" ] || file=./${1:-.}/index.txt
! [ -f "${1:-.}.txt" ]       || file=./${1:-.}.txt
! [ -f "${1:-:}" ]           || file=./${1:-.}

# Fallback to search (allows 'kiss help firefox' to work).
# False positive, intended behavior.
# shellcheck disable=2046
[ "$file" ] || {
    set -f
    set +f -- $(find . -name "${1##*/}.txt")
    file=$1
}

: "${file:=404.txt}"

cat <<EOF - "$file" | "${PAGER:-less}"
Reading $PWD/${file#./}
________________________________________________________________________________

EOF