#!/bin/bash
#<pre><b>
# Script     : greplace
# Version    : 1.0
# Author     : Roland Rashleigh-Berry
# Date       : 21-Sep-2004
# Purpose    : To replace a string with another string in the files listed
#              that are owned by you.
# SubScripts : none
# Notes      : This works on LITERAL text and not regular expressions. Case is
#              important. 
#
#              This script is intended to run on text files such as program code
#              and should not be used for binary files or files with very long
#              record lengths.
#
#              You can only change the files YOU OWN, using this script. Files
#              that do not contain the string to be replaced will not be
#              changed.
#
#              THIS SCRIPT IS DANGEROUS !!!  Do yourself a favour by making
#              backups before using it. Test run it on a dummy file before you
#              use it for real.
#
#              If your target string contains a backslash character ("\") then
#              enclose your target string in single quotes.
#
# Usage      : greplace "this string" "that string" *.sas
#              greplace '\stat\' '/STAT/' *.sas
#              WARNING: Always back up your files before using this
#===============================================================================
# PARAMETERS:
#-pos- -------------------------------description-------------------------------
#  1   Literal target string to replace
#  2   Replacement string
#  3   Files(s)
#===============================================================================
# AMENDMENT HISTORY:
# init --date-- mod-id ----------------------description------------------------
# 
#===============================================================================
# This is public domain software. No guarantee as to suitability or accuracy is
# given or implied. User uses this code entirely at their own risk.
#===============================================================================

iam=$(whoami)

# Edit the test below for the number of expected parameters and put out
# a usage note if an incorrect number supplied. Remove if not required.
if [ $# -lt 3 ] ; then
  echo "Usage: greplace \"target\" \"replacement\" *.sas" 1>&2
  exit 1
fi

target="$1"
repl="$2"

shift 2

echo 
echo "target string: \"$target\""
echo "replacement string: \"$repl\""
echo

for file in "$@" ; do
  owner=$(ls -ld "$file" | gawk '{print $3}')
  if [ "$owner" == "$iam" ] ; then
    if fgrep -s "$target" "$file" ; then
      echo "changing file $file"
      cp -p "$file" ~/greplace_$$.tmp
      gawk '{gsub(target,repl);print $0}' target="${target//\\\\/\\\\\\\\}" \
        repl="$repl"  ~/greplace_$$.tmp > "$file"
    fi
  fi
done

rm -f ~/greplace_$$.tmp