From: "Hal E. Fulton" <hal9000@...>
Date: 2003-07-01T05:58:58+09:00
Subject: Re: OT: Status Display

----- Original Message ----- 
From: "Josef 'Jupp' Schugt" <jupp@gmx.de>
To: "ruby-talk ML" <ruby-talk@ruby-lang.org>
Sent: Monday, June 30, 2003 3:39 PM
Subject: Re: OT: Status Display


> Saluton!
> 
> * Juergen Lang; 2003-06-30, 12:44 UTC:
> > Now my Q: Is it possible with ruby to diplay the percentage of the 
> > current status always on the same position on the screen instead of 
> > seperated by newlines or something like that?
> 
> A very portable way is this:
> 
> rubout = 8.chr * 4
> 0.upto(100) {|i|
>   print rubout unless i == 0
>   printf "%3d%%", i
>   $stdout.flush
>   sleep 1
> }
> 
> rubout is backspace characters that remove the percentage text. At 
> first run it is not written. Afterwards it removes the text already 
> visible (you could output a dummy 0% so that the if statement is not 
> needed). printf does output a three digit percentage (see man 3 
> printf for details on printf). The most important statement is the 
> flush statement.

Someone pointed out to me that in some environments
(perhaps in emacs, for example?) a backspace will
actually be printed as a ^H.

I've always preferred just to do a single carriage 
return at the end, and ensure that my output strings
are all the same length (formatted output) so as not
to leave any "trash" when a short line is printed
over a longer one...

Hal

--
Hal Fulton
hal9000@hypermetrics.com