Returning to your original problem, I would suggest a different approach. This sounds like a problem that has already been solved. If you tell us what program created the offending file, some monk probably could point you to that solution.

If that does not work, specify your problem clearly by posting the following information.

• Code points of the three offending characters
• The hex encoding of each (from the file dump below).
• Code points of the replacements.
• Hex dump of the a segment of the offending file. It should contain at least one sample of each of the three characters.
• Hex dump of the same segment with the required corrections
• (optional)Your best guess of the file encoding.

With this much information, we can suggest Perl solutions that will work.