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Trailing-Edge - PDP-10 Archives - decuslib20-01 - decus/20-0004/whats.tty
There are no other files named whats.tty in the archive.
WHATS

WHATS(FILE) returns an indication of what FILE is, similar
to the SUBSYS by the same name; it knows about SYSOUTs
and MAKESYSs and indirect files and lisp files and .EARS files.

Larry