Distinguishing between ASCII and UTF8

[Richard Gaskin]

I have an app that needs to auto-detect Unicode and plain text, and 
render them correctly based on that auto-detection.

I have the UTF16 stuff working, but with UTF8 I have a problem:  there 
is no BOM to let me know if it's Unicode, and some plain text files will 
occasionally have high-ASCII values in them (like the dagger symbol).

What patterns should I be looking for in the binary data of a file to 
distinguish UTF8 from plain text?

--
  Richard Gaskin
  Fourth World
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