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Can anyone recommend a reverse telnet (connect incoming TCP to a COM port) program for Windows?

Ideally it would run as a system service and listen on an array of TCP ports corresponding to the various COMn serial ports, but I'd also be happy with manually launching and a single port.

Solutions that require cygwin are acceptable. I have nc but I don't know how to launch it to get bidirectional communications.

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up vote 2 down vote accepted

The External Links section of the "COM port redirector" article on Wikipedia has a list of over 20 programs.

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Thanks. socat is promising. Most of that page seems to be describing virtual ports, which is something else entirely. – Ben Voigt Mar 22 '11 at 15:57

It turns out that although netcat requires separate file descriptors for read and write, socat can use a single descriptor.

socat TCPv4-LISTEN:tcpportnum/dev/ttySserialportnum,bbaudrate

works nicely.

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