NAME
ttyn - return name of current typewriter
SYNOPSIS
jsr pc,ttyn
ttyn(file)
DESCRIPTION
Ttyn hunts up the last character of the name of the type-
writer which is the standard input (from as) or is specified
by the argument file descriptor (from C). If n is returned,
the typewriter name is then ``/dev/ttyn''.
x is returned if the indicated file does not correspond to a
typewriter.
BUGS
1