In a message to All 
Eric Theriault  wrote:

 > For finding compressed echo mail, how would be the best algorithm
 > to take?  Would it be to check for *.SU*, *.MO*, etc?

The general accepted file naming convention is xxxxxxxx.ddn, where xxxxxxxx
is any 8-digit hexadecimal number, dd is either SU, MO, TU, WE, TH, FR, or
SA (denoting the day-of-the-week the mail bundle was created), and n a
digit between 0 and 9 inclusive.

 > Also, what would be the best way to detect what compressor was used?

You'll have to read the first few bytes of the bundle and determine its
"signature", comparing it with the signature that each archiver
generates.  If you're a C programmer, the "SNIPPETS" archive
contains archive detection code. For Turbo Pascal, look for the
"SWAG" archive.  If you program in another language, you might be
looking forward to some code translation. :-)

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