Peter Hurley wrote:
On 01/19/2015 02:43 PM, Howard Chu wrote:
The fact that EXTPROC can be manually unset is by design. Quoting from the
original again:
stty.diff:
This file contains the changes needed for the stty(1) program
to report on the current status of the TS_EXTPROC bit. It also
allows the user to turn on/off the TS_EXTPROC bit. This is useful
because it allows the user to say "stty -extproc", and the
LINEMODE option will be automatically disabled, and saying "stty
extproc" will re-enable the LINEMODE option.
This option is not supported by gnu coreutils.
OK. It's in *BSD and Minix. Looks like I never wrote a patch for
coreutils for this last time around.
So it's really back to the question of, does allowing EXTPROC for regular
ttys have _value_?
Does preventing it have value? I like having the option of turning
linemode on and off in a session, for debugging purposes if nothing else.
6. EXTPROC still does some input processing on the server. For example,
7-bit mode (ISTRIP), tolower mode (IUCLC) and processing while
closing; if input processing is being done on the local/client side,
why the extra work here?
That's defensive, on the assumption that something else might break if e.g. the
tty expected only 7-bit input but 8-bit characters were sent to it.
Ok, is that because RFC 1116 doesn't specify ISTRIP and IUCLC handling so
the server can't be sure the client did it? If so, that should be documented
so that refactors don't remove that handling.
Could you get back to me about this, as well?
The telnet protocol (RFC854) defines a Network Virtual Terminal (NVT) as using
7-bit USASCII in an 8-bit field. As such, it expects the client to be able to
generate both upper and lower case itself, so there's no analogue to IUCLC, and
there would be no reason to use ISTRIP.
RFC5198 updates the protocols to use UTF8. So again, it assumes full octets are
being transmitted.
Perhaps we can drop these special cases from the driver.
I don't mind leaving it in, but without comments it looks like a
refactoring error.
I'm working up revisions for the patch.
--
-- Howard Chu
CTO, Symas Corp. http://www.symas.com
Director, Highland Sun http://highlandsun.com/hyc/
Chief Architect, OpenLDAP http://www.openldap.org/project/
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