From:	SMTP%"mark.martinec@NSC.IJS.SI" 10-MAY-1995 21:43:44.62
To:	EVERHART
CC:	
Subj:	Re: Directory scrolling broken in Beta 10?

Message-Id: <199505101004.GAA09229@mx2.smtp.psi.net>
Date:         Mon, 8 May 1995 00:34:52 GMT
Reply-To: Mark Martinec <mark.martinec@NSC.IJS.SI>
Sender: ANU-NEWS Discussion <ANU-NEWS@VM1.NoDak.EDU>
From: Mark Martinec <mark.martinec@NSC.IJS.SI>
Organization: J. Stefan Institute, Lj, Slovenia
Subject:      Re: Directory scrolling broken in Beta 10?
To: Multiple recipients of list ANU-NEWS <ANU-NEWS@VM1.NoDak.EDU>

In article <1995Apr28.222134.3599@hartwick.edu>, wisanr@hartwick.edu (Dick Wisan
) writes:
| In article <1995Apr27.171959.8393@malad2.mala.bc.ca>, dunnett@mala.bc.ca (Malc
olm Dunnett) writes:
| >   It seems the behaviour when scrolling through a directory has
| > changed in beta10. In beta9 if I scroll up or down one item at a time
| > the display is updated using the "scrolled region" feature of the
| > terminal, which is quite fast. With beta10 it appears to redisplay the
| > entire directory listing each time I move the pointer.
| >
| >   Is this a bug or a feature?
|
| Our reader was just updated, and we have the same problem.  It's making
| me seasick.  There must be something you can set to determine how close
| to the top/bottom the cursor gets before it begins to scroll the whole screen.

|
| Does anybody know how to do this?

I would call it a bug, or better still, an unsuccessful attempt
to fix some other problem.  The appended patch reverts the change
in the code and fixes the scrolling - unfortunately another bug
in SMG is revealed. It seems to only affect ANU running on AXP:

> There appears to be a problem in V6.1b10 if you select a non-existing
> group.  It is easy to duplicate.  Start NEWS, then do:
>   NEWS> BOTTOM
>   NEWS> SELECT asdf.fdsa
>   NEWS> TOP
> and NEWS will abort with an access violation.  Somehow the SMG data
> structures are apparently being trashed, because the ACCVIO happens
> inside SMG from the call:
>   if (refresh) c$cks(smg$end_pasteboard_update(&pid));
> in position_display().

So - if you are running on VAX, please apply the patch to fix the
scrolling.  If running on AXP, you must decide to either fix the
scrolling and break SMG on a rare occasion, or leave it as it is.

Better still - find out what is going on - a true solution would be
most welcome !


----cut-here---------------------------------------------------
*** [anu-news.news_src]newsutility.c;1
--- newsutility.c
**************
*** 3411,3417
          else *cp = (devrow - (9 + p));
          }
  ----------------------------------------*/
!     if (refresh) c$cks(smg$begin_pasteboard_update(&pid));
!     _c$cks(smg$move_virtual_display(vd,&pid,cp,c$ac(1),0));
!     if (refresh) c$cks(smg$end_pasteboard_update(&pid));
  }
--- 3411,3417 -----
          else *cp = (devrow - (9 + p));
          }
  ----------------------------------------*/
!     if (refresh) c$cks(smg$end_pasteboard_update(&pid));
!     _c$cks(smg$move_virtual_display(vd,&pid,cp,c$ac(1),0));
!     if (refresh) c$cks(smg$begin_pasteboard_update(&pid));
  }
----cut-here---------------------------------------------------


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