replicate by: open acme on a file of length 8215 bytes, position
the cursor at the end, and right-click-search for a string
that isn't in the file... and it'll go into an infinite
loop. it happens whenever the buffer read is exactly one short of
the end of the file.

i think this bug has probably been around from day 1,
which is interesting, because it's not *that* improbable an event...