#!/usr/bin/env python
#---------------------------------------------------
# This program searches for a word in list of files
# and replace it with another word.
#---------------------------------------------------

import os
import sys
import re

def usage(msg):
    sys.stderr.write("This script attempts to search a word in a provided\n")
    sys.stderr.write("list of files and replace it with another word.\n")
    sys.stderr.write("\n ")
    sys.stderr.write("Usage:\n")
    sys.stderr.write("   %s %s\n" % (sys.argv[0], msg))
    sys.exit(1)

n = len(sys.argv[1:])
if (n < 3):
   usage('oldWord newWord file1 file2 file3 ...')


#-----------------------------------
# Get the words from the command line
#-----------------------------------

oldWord = str(sys.argv[1])
newWord = str(sys.argv[2])

#-------------------------------------------
# Start the search by looping over the files
#-------------------------------------------

for fName in sys.argv[3:]:
    data = open(fName).read()
    open(fName,"w").write( re.sub(oldWord,newWord,data) )