3.0.5: PROMPT and output on the same line

3.0.5: PROMPT and output on the same line

[Jos Backus]

hal:/usr/src# zsh -f
hal# echo -n hi
hal# sh
# echo -n hi
hi# csh -f
# echo -n hi
hi# tcsh -f
# echo -n hi
hi# ksh
# echo -n hi
hi# exit

Note that between lines 2 and 3, there's no ``hi''.

This is on FreeBSD -current, using the stock /bin/{c,}sh, pdksh-5.2.13 and
tcsh-6.08.00.

Cheers,
-- 
Jos Backus                          _/  _/_/_/    "Reliability means never
                                   _/  _/   _/     having to say you're sorry."
                                  _/  _/_/_/               -- D. J. Bernstein
                             _/  _/  _/    _/
Jos.Backus@nl.origin-it.com  _/_/   _/_/_/        use Std::Disclaimer;

Re: 3.0.5: PROMPT and output on the same line

[Jos Backus]

On Wed, Mar 31, 1999 at 10:29:33AM +0200, Sven Wischnowsky wrote:
> % zsh -f
> beta% echo -n ho
> beta% setopt nopromptcr
> beta% echo -n ho
> hobeta%
 
Grr, I searched the manpages for 'newline' but didn't see anything relevant.

> Maybe this should be in the FAQ.

I agree, especially because zsh's default behavior differs from a number of
other shells at least. A colleague of mine pointed this behavior out to me the
other day when I was doing some zsh evangelizing.

Thanks, Sven!

-- 
Jos Backus                          _/  _/_/_/    "Reliability means never
                                   _/  _/   _/     having to say you're sorry."
                                  _/  _/_/_/               -- D. J. Bernstein
                             _/  _/  _/    _/
Jos.Backus@nl.origin-it.com  _/_/   _/_/_/        use Std::Disclaimer;

Re: 3.0.5: PROMPT and output on the same line

[jr]

>hal:/usr/src# zsh -f
>hal# echo -n hi
>hal# sh
># echo -n hi
>hi# csh -f
># echo -n hi
>hi# tcsh -f
># echo -n hi
>hi# ksh
># echo -n hi
>hi# exit
>
>Note that between lines 2 and 3, there's no ``hi''.
>
>This is on FreeBSD -current, using the stock /bin/{c,}sh, pdksh-5.2.13 and
>tcsh-6.08.00.

Using script, I get this:

Script started on Wed 31 Mar 1999 09:24:59 BST
^M^[[m^[[m^[[m^[[Jair% ^[[Kl^H ^He^Hecho -n hi^M^M
hi^M^[[m^[[m^[[m^[[Jair% ^[[Ke^Hexit
script done on Wed 31 Mar 1999 09:25:08 BST

Basically, zsh puts some control characters at the start of the prompt, 
forcing itself to the start of the line.  This also happens with:
#!/usr/local/bin/perl
print "hello";

Since there is no \n, the prompt overwrites the "hello".

Also:
air% echo -n hi; echo ""
hi
air% 

The second echo sends a newline, and the "hi" is visible.

I don't know whether to consider this action a bug or a feature;  certainly, 
it's easy enough to work around and probably simple enough to patch a fix for 
(simply remove the control characters before printing $PS1)

-- 
John Riddoch	Email: jr@scms.rgu.ac.uk	Telephone: (01224)262730
Room C4, School of Computer and Mathematical Science
Robert Gordon University, Aberdeen, AB25 1HG
I am Homer of Borg. Resistance is Fu... Ooooh! Donuts!

Re: 3.0.5: PROMPT and output on the same line

[Sven Wischnowsky]

Jos Backus wrote:

> hal:/usr/src# zsh -f
> hal# echo -n hi
> hal# sh
> # echo -n hi
> hi# csh -f
> # echo -n hi
> hi# tcsh -f
> # echo -n hi
> hi# ksh
> # echo -n hi
> hi# exit
> 
> Note that between lines 2 and 3, there's no ``hi''.
> 
> This is on FreeBSD -current, using the stock /bin/{c,}sh, pdksh-5.2.13 and
> tcsh-6.08.00.

% zsh -f
beta% echo -n ho
beta% setopt nopromptcr
beta% echo -n ho
hobeta%

Maybe this should be in the FAQ.

Bye
 Sven


--
Sven Wischnowsky                         wischnow@informatik.hu-berlin.de