Replace a file reading from another file

Shell Programming and Scripting
1

Hi Guys,

I have a file which has string which needs to be replaced by what.

Change.txt
Former   Replace with
ASD       AAD
ABP        NAID

I like to read this file and search another file and replace the content.
For an example, read Change.txt and replace ASD with AAD in the source file.

Could somebody help me with.

Cheers!!!!!!!!!!!

2

I am just curious about:

  1. how big is your source file
  2. how many rows(substitution pair) you have in change.txt
3

My Source is 4700 lines long..

Each line in the change.txt will appear within 10 times in the file. The Change.txt has 45 words which needs to be replaced.

Hope that helps