expr

#!/bin/sh

# Adds "--" before 1st unknown parameter starting with "-"

#echo /bin/expr "$@" >&2

known="--help --hel --he --h --version --versio --versi --vers --ver --ve --v"
known="$known --bignum --bignu --bign --big --bi --b --no-bignum --no-bignu --no-bign --no-big --no-bi --no-b --no- --no --n"

starting=

while [ "$1" ]; do
  case "${1}" in
  -- )
    break
    ;;
  -* )
    found=
    for k in $known; do
     [ "$1" = "$k" ] && { found=y; break; }
    done
    if [ -z "$found" ] ; then
      starting="$starting --"
      break
    fi
    ;;
  * )
    break
    ;;
  esac
  starting="$starting $1"
  shift
done

#echo /bin/expr $starting "$@" >&2
/usr/bin/expr $starting "$@"