mime_longlines - generate a test message with long lines
-s Stringify message first, and print the *string* to STDOUT.
Assemble and print (to the standard output) a multipart message with 5 attachments, for the purpose of "eyeballing" how well the encoders are working.
Each attachments holds the same data -- some 8-bit text, and a long line consisting of 1000 "a"s followed by a few "b"s) -- but each has a different encoding (the "Content-transfer-encoding" field will tell you which is which).
All of the encodings (except for the first one, "binary") should break the long line before the b's.