Hi!
I recently came across an ancient issue related to the ambiguity in
interpreting
the escape key in terminal applications. The problem lies in
distinguishing the
escape key "\x1b" from ANSI escape sequences (e.g., "\x1b[A" for the up
arrow).
Traditionally, this issue has been addressed by measuring the time gap
between
receiving the initial escape character "\x1b" and the following "[A". If
there
is a noticeable delay between them, they are considered as separate keys
(ESC,
'[', and 'A'). Otherwise, they are treated as a single up arrow key
press.
While this time-based approach works well for locally executed terminal
applications, telnet applications are still affected by network latency
issues.
To tackle this, I suggest enabling the negotiation of the Telnet End of
Record
Option in the Inetutils telnet client. Currently, the client does not
seem to
support this option effectively. Although some handling exists in the
source
code, it appears to be activated only when the TN3270 macro is defined.
If the telnet client could send an IAC EOR 2-octet sequence after each
key
press, the ambiguity could be easily resolved, at least in character
mode
transmission.
Erich
