serial port: fconfigure -handshaking fails

System: FreeBSD 6.1-RELEASE
Tcl/Tk Version: 8.4

Running the following:


# open the serial port...
set f [open /dev/cuad0 r+]
# set bidirectional (RFR/CTS) flow control
fconfigure $f -handshaking rtscts

Results in

bad option "-handshaking": should be one of -blocking, -buffering,
-buffersize, -encoding, -eofchar, or -translation

According to posts I've read here, this should work (I'm assuming here,
since from what I've read rfrcts isn't available as one of the four
options, that rtscts is, in fact, bidirectional, and not the older,
unidirectional RTS/CTS, since the latter went the way of software
flow control---into the ancient-history files).

Can anyone see what I'm doing wrong here?

Thanks,
--jim

--
73 DE N5IAL (/4) MiSTie #49997 < Running FreeBSD 6.1 >
spooky130@xxxxxxx ICBM/Hurricane: 30.39735N 86.60439W

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