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Re: how to get zsh to work with a screen reader



OK, thanks.  So what does bash do differently?  It does not give me the problem,
I wonder if it tries to do cursor movement instead of reprinting?

Thanks again for your response.

Bart Schaefer <schaefer@xxxxxxxxxxxxxxxx> wrote:

> On Jul 21,  2:37pm, covici@xxxxxxxxxxxxxx wrote:
> } Subject: how to get zsh to work with a screen reader
> }
> } when I use zsh, I hear the entire line repeated when I do a completion,
> } or after I type a carriage return, I hear the line I just typed, even
> } though there is not an extra copy on the screen.  So what I was
> } wondering, is if zsh is writing the whole line out under many conditions
> 
> The ZLE editor does not use the curses package for screen optimization,
> so among other things if the cursor is at column X and needs to move
> across some existing text to column X+10, ZLE may reprint the characters
> rather than emit a cursor movement command.
> 
> It will also prefer to overstrike a region with the text that is meant
> to appear there, rather than to assume the text is already visible and
> simply move past it, because it does not attempt to maintain an internal
> data structure that reflects the contents of the screen -- it only keeps
> a data structure for the text of the prompt and the contents of the edit
> buffer.  So any time it wants the screen and the buffer to match, the
> only way it can be certain that is true is to reprint everything.
> 
> The assumption is that the terminal emulator will either optimize out
> unnecessary redrawing, or be fast enough that it doesn't matter.  That's
> obviously not the case for a text-to-speech translator that interposes
> between the shell output and the terminal.
> 
> Sadly, there's no practical approach I can think of to rectify this.

-- 
Your life is like a penny.  You're going to lose it.  The question is:
How do
you spend it?

         John Covici
         covici@xxxxxxxxxxxxxx



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