What have you tried?

Not knowing which part has got you down, the quick break down is: open the input and output files, loop through them, change each line based on a regular expression that does what you want, print the changed line to the output file, and then close both file handles before exiting.

Most of this is taken care of if you use something like perl -pie 's/regexp/change/' filename. So the real problem is - what is the regular expression?

That depends on the spec. "As you can see" - I thought you just wanted to change "turkey" to "fox" until the last line - so it wasn't very obvious to me.

In your case, I would suggest code like this: 

    s/\S+(\s*)$/new-word$1/ if /elephant \* [/a-zA-Z]/

[download]
(the "last word" may not actually end the line - spaces after the last word doesn't change the fact it's the last word) The reason I didn't go with: 
    s/(elephant \* [/a-zA-Z].*?\s)\S+(\s*)$/$1new-word$2/

[download]
is because you don't always have more than one word following the *, and I couldn't think of a quick, easy, obvious way to do it in a single regex. Since everything is anchored, this shouldn't be much different in speed, but, more importantly, it should be correct.

In reply to Re: Changing the contents of a file by Tanktalus
in thread Changing the contents of a file by perlNinny

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