Does ssh use telnet options?

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Telnet options are escape sequences sent between telnet client and
server invisibly to the user, to control things like terminal window
size (width and height), echoing, suppress go ahead, terminal type (a
string), line mode, and so forth.

When using ssh to login to a remote server, does ssh also use telnet
options invisibly?  We write software that speaks to telnet sessions,
and as we migrate to ssh, I can't seem to find whether or not I need
to support the same telnet options.

If ssh doesn't use telnet options, how are things like window size
communicated to the remote server so vi or less or other things know
your window size?  I've searched a long time and can't seem to find
the answer.  Thanks for any help!

Re: Does ssh use telnet options?

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No, it doesn't, but the SSH protocol contains its own messages which
do many of the same things.

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Your definitive reference for this sort of question iks the
specifications for the SSH protocol: RFC 4521-4254 inclusive. RFC
4254 is likely to contain most of what you're after.

You mentioned window size as an example. This is dealt with in two
places in RFC 4254: section 6.2 describes the SSH message which sets
up a terminal device on the server, in which the client also
specifies the starting window size, and section 6.7 describes the
SSH message which the client sends in mid-session to indicate that
the window size has changed.
Simon Tatham         "infinite loop _see_ loop, infinite"

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