For example, if the default keyboard map and the default STRTCPTELN command
parameters are in effect, the VTxxx Control-C function can be entered by typing &C
followed by pressing the F11 key.(It can also be entered simply by <F12> using the
default keyboard map, but in case you are using an application where <F12> is
remapped, this example is included, and illustrates the principle of the
*SENDWOCR key.
The character used to indicate a control character can be selected on the
CTLCHAR parameter of the STRTCPTELN command. The default is &. The &C
characters must be the last characters typed before pressing the *SENDWOCR
function key or the &C is not interpreted as a control character.A control character is
only sent when the *SENDWOCR function key is pressed. Youcan assign
frequently used VTxxx control characters to a function key.An example of the Ctrl-C
command can be described as follows. When using Telnetclient to connect to an
RS/6000 system, VT220 emulation will typically be negotiated. The Ctrl-C sequence
is an important one in AIX to end long running commands, such as PING. It is,
therefore, important that you know how to do this before issuing any RS/6000
commands. By default the sequence is &C <F11>. Note that these keys have to be
entered quickly, and it may take several attempts before the RS/6000 task accepts
the input.
If you do not want the characters that are being typed to be displayed, the function
key associated with the *HIDE function should be pressed (F6 on the default
keyboard map). This function should be used when typing a password.
If you want the characters that have been typed to be sent to the remote system for
processing without pressing the Enter key, you should press the function key
associated with the *SENDWOCR function (F11 on the default keyboard map).
It is often useful to be able to recall previously entered commands. On the AS/400
F9 often provides this function. On AIX, this can be activated by typing the
command set -o vi and pressing Enter.After this, you can start retrieving commands
with the sequence EscK. Toperform this sequence using the default keyboard map
while in VTxxx emulation, you should use the sequence <F5>k<F11>.The Esc
character starts the command retrieval. The k can then be used to retrieve further
commands. While operating in this mode, the commands H for right, L for left, X for
delete, I for insert, and R for replace apply.The sequence <F5>i<F11> switches this
facility off.
Screen Issues
The character in the position just before the cursor position will always be blank.
The actual character is saved internally and is displayed when the display is
refreshed with the cursor in a different position.
A VTxxx application that uses row 1, column 1 of the display does not work the
same when using AS/400 Telnetclient support. Most 5250-type display stations do
not allow input to row 1, column 1. If the VTxxx application positions the cursor at
row 1, column 1, the AS/400 system puts the cursor at row 1, column 2,
automatically.
Due to architectural differences, certain VTxxx commands or sequences are not
supported and are ignored. An example is downstream loadable character sets.
Chapter5. TelnetClient 165