Bug or Feature? Clear line before prompt.

Bug or Feature? Clear line before prompt.

[Com MN PG P E B Consultant 3]

Before zsh issues the PS1 prompt, it clears the line. This has the
effect that
I don't see the last line of the previous command, unless it is
terminated
by a newline. Example:

   perl -e 'print "hello"'

does not show the output "hello", because it is erased immediately by
the shell, but

   perl -e 'print "hello\n"

shows, because the output is terminated by \n.

My setting of PS1 is:  %B%~%b>

Is there a way to tell zsh not to erase the line before writing the
prompt?

Ronald

-- 
Ronald Fischer <mn-pg-p-e-b-consultant-3.com@siemens.com>
 

Re: Bug or Feature? Clear line before prompt.

[Steve Borho]

On Fri, 2005-10-14 at 08:16 +0200, Com MN PG P E B Consultant 3 wrote:
> Before zsh issues the PS1 prompt, it clears the line. This has the
> effect that
> I don't see the last line of the previous command, unless it is
> terminated
> by a newline. Example:
> 
>    perl -e 'print "hello"'

% echo -n foo
% unsetopt prompt_cr 
% echo -n foo
foo%

Note that turning this option off can do some bad things to the command
line editor and many of the fancier prompts.

--
Steve

Re: Bug or Feature? Clear line before prompt.

[Wayne Davison]

On Fri, Oct 14, 2005 at 08:16:36AM +0200, Com MN PG P E B Consultant 3 wrote:
> Is there a way to tell zsh not to erase the line before writing the
> prompt?

This is taken from the FAQ:

  A better solution than disabling PROMPT_CR (for most terminals) is adding
  a simpler version of the PROMPT_SP (new in 4.3.0) functionality to an
  older zsh using a custom precmd function, like this one:

    # Skip defining precmd if the PROMPT_SP option is available.
    if ! eval '[[ -o promptsp ]] 2>/dev/null'; then
      function precmd {
        # Output an inverse char and a bunch spaces.  We include
        # a CR at the end so that any user-input that gets echoed
        # between this output and the prompt doesn't cause a wrap.
        print -nP "%B%S%#%s%b${(l:$((COLUMNS-1)):::):-}\r"
      }
    fi

  That precmd function will only bump the screen down to a new line if there
  was output on the prompt line, otherwise the extra chars get removed by
  the PROMPT_CR action.  Although this typically looks fine it may result
  in the spaces preceding the prompt being included when you select a line
  of preserved text with the mouse.

..wayne..

Re: Bug or Feature? Clear line before prompt.

[DervishD]

    Hi Ronald :)

 * Com MN PG P E B Consultant 3 <mn-pg-p-e-b-consultant-3.com@siemens.com> dixit:
> I don't see the last line of the previous command, unless it is
> terminated
> by a newline. Example:
> 
>    perl -e 'print "hello"'
> 
> does not show the output "hello", because it is erased immediately by
> the shell, but
> 
>    perl -e 'print "hello\n"
> 
> shows, because the output is terminated by \n.
> 
> My setting of PS1 is:  %B%~%b>
> 
> Is there a way to tell zsh not to erase the line before writing the
> prompt?

    You can always "unsetopt prompt_cr", but I find this one much
more useful:

    # After you've set your PS1
    PS1=$'\n'"$PS1"

    This prints a newline before the prompt itself. You can achieve
this with precmd, too, you can make it print a newline if there is
text on the current line (I think you can know that in Linux using
/dev/vcs), or if the cursor is in the last column, etc. For me adding
a newline character just before my PS1 is enough.

    Raúl Núñez de Arenas Coronado

-- 
Linux Registered User 88736 | http://www.dervishd.net
http://www.pleyades.net & http://www.gotesdelluna.net
It's my PC and I'll cry if I want to...