Pyramid xterm (premature file closure?) bug

[Bob Sutterfield]

In an X11R3 xterm client running on a Sun (or anything else I've got
to test with), when I say
	cat < /dev/tty
the cat will wait indefinitely for me to type something.  When I type
a carriage return, that line is echoed.  This continues until I type
my eof character, when I get my shell prompt back.  $status==0.

In an xterm client running on a Pyramid, `cat < /dev/tty' exits
immediately, returning me to my shell.  $status==0.

This is quite frustrating when running applications like the stock su
or an FTP client, or any other that takes the easy way out and opens
/dev/tty for reading.

X11R3 xterm on most everything but a Pyramid works correctly in this
respect.  X10R4 xterm had exactly the same behavior: correct
everywhere but on a Pyramid.  (I had hoped the problem would go away
in X11, but I guess not...)

I'm not complaining about Pyramid's support or anything like that,
because I'm running the MIT code and we haven't paid Pyramid for their
commercial-grade bulletproof X port, so we don't have it.  I'm just
curious whether anyone has already solved this one and is willing to
share their solution for free, or whether it's time to dive into a
Pyramid xterm with dbx (again).

Any clues?