in reply to Replace Whitespace with Comma

It looks like your input is fixed-width. If so, use unpack and join:
use warnings; use strict; while (<DATA>) { my @cols = unpack 'A8A11A9A9A*', $_; print join(',', @cols), "\n"; } __DATA__ 12345 DOE,JOHN $50.00 REFUND COMPLETE 12345 DOE,JOHN $25.00 DENIED COMPLETE 12345 DOE,JOHN $75.00 COMPLETE 12345 DOE,JOHN $10.00 REFUND COMPLETE