messaging function needs to use uftc_open()

[trothr]

The interactive message sending function should use uftc_open() rather than tcpopen() directly.
This will let it (among other things) connect via proxy.

msgc.c will also need modification to support a "--proxy" option.

[trothtech]

done!
uftc.c now drives uftc_open() when establishing a connection with the target UFT server or host.
And, yes, the 'tell' command now has a --proxy option as naturally follows.