Re: keyboard questions. -- LINUX5250

On Thu, 3 Jul 2003 Phillip.Watts@xxxxxxxxx wrote:

> 1.  My understanding is that if I leave .Xdefaults alone the other
>        apps will be unaffected by, for instance, my mapping
>         Enter to Field Exit.   If I do that mapping in
>         /usr/share/tn5250/XTerm,
>         it will take care of the 5250 sessions and not affect anything
>         else.  ??

.Xdefaults contains configuration information about many applications.
For example, emacs settings are identified in .Xdefaults like this:

#ifdef COLOR
emacs*Background                : black
emacs*BorderColor               : blue
emacs*cursorColor               : red
emacs*Foreground                : white
emacs*pointerColor              : yellow
#endif /* COLOR */

emacs*BorderWidth               : 12
emacs*Font                      : 9x15
emacs*Geometry                  : 80x35

Of course you may not have any settings for emacs in your .Xdefaults and
that's fine, you don't have to.  In fact, you don't need a .Xdefaults at
all for this to function (but don't delete it if you have it).

So adding settings for other apps in .Xdefaults doesn't affect the rest of
your application - you can do pretty much whatever you want without
screwing things up.  tn5250 identifies itself in .Xdefaults by xt5250.
Anything that start with xt5250* only affects tn5250.  So following the
information in the tn5250 HOWTO won't hurt any other applications.

http://www.chowhouse.com/~james/tn5250-HOWTO.pdf

> 2.  My (barely) understanding is that  the default(?)  file
>       ...../i386/qwerty/us.kmap.gz
>       maps  scancodes to 'names'  like   Escape or KP_ADD.
>       then a filter file like XTerm can use those 'names'  to map to ascii
>       sequences.  ??
>       If that is correct, what does the mapping in lieu of XTerm?
>        and what happens to all the keys which XTerm doesn't map?
>        Is XTerm an override of a broader mapping?  Pardon my ignorance.

XTerm (I assume you mean the file /usr/local/share/tn5250/XTerm) doesn't
have anything to do with us.kmap.gz.  The XTerm file and .Xdefaults only
affect tn5250 when run in X Windows using xt5250.  us.kmap.gz is only used
with tn5250 when run from the console using the loadkeys command.  Since
you want to run tn5250 (really xt5250) in X along with all your other
apps, just forget about loadkeys and us.kmap.gz.  Either modify your
.Xdefaults file or /usr/local/share/tn5250/XTerm.

> 3.  The next step in the process would be what is sent to the AS400.
>        As far as data, should I just assume that if the proper CodePage is
>        selected, the correct ascii/ebcdic  and  ebcdic/ascii translation will
> occur?
>        I am aware for instance there are subtle differences between
>        Spanish(Spain)  and Spanish Speaking(Mexico).  Not that that particular
>        one affects me.

There is a map argument that specifies what codepage you want to use.  It
needs to be set to be the same as whatever your AS/400 is already using.

> 4. Back to scancodes.
>            There are keys which need to act differently.  Like Right control
>    and Left control.  If I use us5250.map (which looks like a more thorough
>    mapping than us.kmap.gz.  Would I do a loadkeys?
>    Then if I map Right Control to  5250 Enter (which is what my users are used
>    to)
>    would other apps  lose that a ctrl key?  Again pardon my ignorance.

Again, since you want to run tn5250 in X, don't worry about loadkeys or
us5250.map.  Those don't do anything when in X.  Modify either .Xdefaults
or /usr/local/share/tn5250/XTerm.  Modifying either of these files won't
affect your other applications.

James Rich