On Unix: 
perl -pi.bak -e 's/(.*),(.*)/$2 $1/' test.txt

[download]
Windows uses " instead of '.

Beyond that, have an indentation style, check $! on open, and it usually winds up being a bad idea to edit files in place - leave the original and write a copy. (Or at least keep a backup as I did above.)

In reply to Re: Refining my Program by Anonymous Monk
in thread Refining my Program by EmmittSmith

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