NetNews Usenet Archive 1993 #1/NN_1993_1.iso/spool/comp/os/vms/20479

Internet Message Format | 1993-01-06 | 1.8 KB

Path: sparky!uunet!portal!cup.portal.com!Chris_F_Chiesa
From: [e-mail]
Newsgroups: comp.os.vms
Subject: Re: Question: Reading keys with command procedures.
Message-ID: <[e-mail]>
Date: Wed,  6 Jan 93 18:27:19 PST
Organization: The Portal System (TM)
Distribution: world
References:  <[e-mail]>
Lines: 30

David Gitlin ([e-mail]) writes:

>Is there any way to get a command
>procedure to read a single key stroke without the user having to hit
>enter/return. This would be useful under several conditions. Also can you read
>arrow keys under DCL command procedures. [...]
>
>(P.S. I know you can do this easily via any programing language like Macro,
>C, etc I want to know if it can be done strictly from DCL command procedures.)

Strictly speaking, NO.  There's no native "get a raw keystroke" verb in
DCL.

It's easy to implement your own, though -- as you have already noted, it's
easy to "get a keystroke" in any compilable language, and it's also easy to
assign the obtained keystroke (I recommend VAX BASIC if you have it, because
its INKEY$ function implicitly parses the function keys for you and returns
strings such as "UP" for the up-arrow, "DOWN" for the down-arrow, etc. (as
distinguished from you typing D,O,W,N, which would generate a "D" the first
time you called INKEY$, an "O" the second time, etc., e.g.) to a DCL symbol.

   (I've implemented a GETKEY verb any number of times; hasn't everybody?
:-)  I even went to the extreme of implementing a system of menus with a
keystroke-controlled, SMG$-style highlight cursor, in DCL with a homegrown
GETKEY verb - but I don't recommend it, as it was too slow-responding to be
practical...  And before anyone asks, no, I no longer have this code.  I'd
hand it out if I had it, but I don't.)

  Chris Chiesa
    [e-mail]