Programming CTS/RTS on serial ports directly

[Ben Dugan <bdugan@netaxs.com>]

I'm trying to use the CTS/RTS signals to control external hardware
(but not as handshaking lines in the usual sense).

Since they weren't intended to be used that way, I'm getting the
feeling there's no way to directly interface with them through the GNU
C library.  In any case, I haven't been able to find references to
CTS/RTS, except for ways to enable CTS/RTS handshaking.  That
handshaking is then handled at a lower level, but I can't see how I
can get at the signals themselves.

Any tips (even where to look for more info) would be very helpful; thanks.

Ben