#!/usr/bin/env bash

# @(#) s1       Demonstrate (GNU) sed substitution of nth occurrence of string.

echo
set +o nounset
LC_ALL=C ; LANG=C ; export LC_ALL LANG
echo "Environment: LC_ALL = $LC_ALL, LANG = $LANG"
echo "(Versions displayed with local utility \"version\")"
version >/dev/null 2>&1 && version "=o" $(_eat $0 $1) sed
set -o nounset
echo

FILE=${1-data1}

echo " Data file $FILE:"
cat $FILE

echo
echo " Results:"
sed -e 's/ /,/4' -e 's/ /=/3' -e 's/ /;/2' -e 's/ /@/1' $FILE

exit 0

% ./s1

Environment: LC_ALL = C, LANG = C
(Versions displayed with local utility "version")
OS, ker|rel, machine: Linux, 2.6.11-x1, i686
Distribution        : Xandros Desktop 3.0.3 Business
GNU bash 2.05b.0
GNU sed version 4.1.2

 Data file data1:
a b c d e
x y z

 Results:
a@b;c=d,e
x@y;z