For the past day or so I've been working through issues to add/change or delete strings in multiple files. As usual there is plethora of methods to do try. Each have a place in an administrator's arsenal.

Using Perl or SED

These methods are suited for text manipulation where search and replace strings are simple without the need for escape characters;

In the following example we replace the word rabbit with the word blueberry in all html files in the current directory;

Of course, there are an abundance of switches that can be used to accomplish more tasks like backing up files before actually executing the search replace function. Check the man pages for more details.

Using RPL