On Tue, 11 Jul 2000, Jeff Waugh wrote:
> Disclaimer: Please don't flame the newbie.
>
> With recent discussions about termcaps, etc. I started thinking about
> the relative obscurity of all these configuration details...
>
> Why do they still exist? How *practically* useful are they anymore?
That's a good question. Others have already mentioned things
like Wyse terminals and remote telnets.
You could actually take all the capabilities out of the server
(the Linux box) and force them into the client (the terminal
emulation program).
Probably at this point the main difference would be between
keyboards. There are other keyboards with different layouts
to IBM PC. I can think of Sun keyboards, and VT100 with their
'application' keys. Luke mentioned Tcl/Tk. This system has
embedded the X type modmap names and modifiers.
I guess the overhead is not that great to have it in. Where it
is unneccasary, it is not big deal to rip it out, say for embedded
or low memory systems.
The thing is, there was no possible way you could encapsulate all
terminal / keyboard behaviour in a table.
Here are some examples from the O'Reilly book:
kdl1 = delete line
xenl = newline glitch
ked = clear to end of screen
There are glitch parameters, support for copy, move, redo, resume,
next object and select keys. Support for standout, blinking, hidden
display characteristics. Any terminal manufacturer could invent
any wierd feature.
I even invented one myself. I made a PC terminal emulation that
would display, buffer but not transmit normal keystrokes (e.g.
A-Z, 0-9) until a special keystroke was entered (e.g. RETURN, TAB or
cursor key). Why? Well a server dealing with hundreds of terminals
only had to respond once per field instead of each character
per field.
One reason these were so important was not for programmers,
but because data entry was done through 'green screens' or terminals.
Data entry was a huge business.
Most people using 'modern' GUI computers have no idea how efficient data
entry and searching is using a text mode terminal. Although this fact is
attested to and rediscovered daily by lynx and w3m users, there are
legions of people in powerful positions who dictate that productivity is
only to be achieved using graphical systems with mouse pointers.
But perhaps Jeff is right. Perhaps it's anachronistic to be carrying
around a personal museum / shrine to the past glories of terminals.
Perhaps we can keep a VT100 terminfo / termcap 'fooler' for apps
that need it. For those who really need to know about the Hazeltine
tilde glitch (hz in terminfo and termcap), well you can roll your
own.
Sic transit gloria.
(As I type this in Pine, the bottom of my xterm has
^G Get Help ^X Send ^R Read File ^Y Prev Pg ^K Cut Text ^O Postpone
^C Cancel ^J Justify ^_ Alt Edit ^V Next Pg ^U UnCut Text^T To Spell
I wonder if Pine is looking up soft keys, or trying to set the status
line. The ^? characters are highlighted, bet that mode is controlled
by a terminfo entry.
Wonderful Pine. How many times have I used you? What a tribute
to commonsense and the 'right way'.)
Nah, lets keep terminfo. The past deserves respect, it
contains the keys of the future. Practicality? I'd vote yes.
Jamie
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