shell prompt undesired characters

shell prompt undesired characters

[Dan Davison]

I am having trouble getting a clean prompt with bash running under M-x
shell. Each line in the shell starts with

^[]0;~\a

(
I don't know how those two control characters will appear to you; what I
see in my emacs buffer is
^[]0;~^G
)

This is true if I set PS1='', so I believe my problem is not related to
escape characters in $PS1 (in fact they work fine if I use them).

I have tried with the system default .bashrc and the problem
persists. However, if I change to sh, then I get a normal, clean prompt
that displays just the contents of PS1.

Where are the strange initial characters above coming from when I run a
bash shell in emacs and how can I fix it?

Thanks a lot,

Dan
emacs 23.0.60.1
ubuntu 8.10

Re: shell prompt undesired characters

[Peter Dyballa]

Am 08.04.2009 um 19:00 schrieb Dan Davison:

> Where are the strange initial characters above coming from when I  
> run a
> bash shell in emacs and how can I fix it?


In ~/.emacs_bash you can set many things for a bash interpreter  
running *shell* buffer (similarly for sh, csh, tcsh, ksh, ...). The  
partial ANSI Esc code you gave looks like a reset/set normal of  
previous colour or effect setting. It might work better when you add:

     (add-hook 'shell-mode-hook (lambda ()
         (ansi-color-for-comint-mode-on)))

--
Greetings

   Pete

There's no place like 127.0.0.1
			– origin unknown

Re: shell prompt undesired characters

[Peter Dyballa]

Am 08.04.2009 um 19:00 schrieb Dan Davison:

> ^G


This is a BEL sound.

--
Greetings

   Pete

A morning without coffee is like something without something else.

Re: shell prompt undesired characters

[Dan Davison]

Peter Dyballa <Peter_Dyballa@web.de> writes:

> Am 08.04.2009 um 19:00 schrieb Dan Davison:
>
>> Where are the strange initial characters above coming from when I
>> run a
>> bash shell in emacs and how can I fix it?
>
>
> In ~/.emacs_bash you can set many things for a bash interpreter
> running *shell* buffer (similarly for sh, csh, tcsh, ksh, ...). The
> partial ANSI Esc code you gave looks like a reset/set normal of
> previous colour or effect setting. It might work better when you add:
>
>     (add-hook 'shell-mode-hook (lambda ()
>         (ansi-color-for-comint-mode-on)))


Thanks, but unfortunately that doesn't solve it. I've tried without any
~/.emacs and ~/.bashrc, on emacs22, and I still get those initial
characters. They're not coming from $PS1, so where are they coming from?

Dan

>
> --
> Greetings
>
>   Pete
>
> There's no place like 127.0.0.1
> 			– origin unknown

Re: shell prompt undesired characters

[Peter Dyballa]

Am 08.04.2009 um 19:53 schrieb Dan Davison:

> I've tried without any
> ~/.emacs

I mentioned ~/.emacs_bash – it only customises bash when run inside  
*shell* buffer. And this file is more useful than a car because it  
can switch off so many things that are fine in a (dumb) terminal  
emulation which GNU Emacs can do better.

> and ~/.bashrc, on emacs22, and I still get those initial
> characters.

Bash uses much more files, see 'man bash' or other bash documentation  
(obviously there are good reasons why I don't use bash by default).

> They're not coming from $PS1, so where are they coming from?


Can you also check the meaning of PS1 in GNU Emacs's *shell* buffer?  
In a terminal I have

	PS1='\e[34;47;1m\j-\[\033[0;32m\]ttyp\[\033[0;31m\]://\[\033[0;32m\] 
pete\[\033[0;31m\]:5\[\033[0;34m\]${PWD/$HOME//~pete}\e[33;46;1m \! /\ 
\ \[\033[0m\]'

in *shell* buffer it's

	PS1='\h:\w \u\$ '

Thanks to ~/.emacs_bash, which does not contain ELisp but shell code:

	PATH=$(defaults read "${HOME}/.MacOSX/environment" PATH)
	MANPATH=$(defaults read "${HOME}/.MacOSX/environment" MANPATH)
	PS1='\h:\w \u\$ '
	unset DYLD_LIBRARY_PATH
	BASH_ENV=${HOME}/Library/init/bash/aliases.mine

--
Greetings

   Pete

They that can give up essential liberty to obtain a little temporary  
safety deserve neither liberty nor safety.
		-Benjamin Franklin, Historical Review of Pennsylvania.

Re: shell prompt undesired characters

[Alex Bennee]

2009/4/9 Dan Davison <davison@stats.ox.ac.uk>:
> Thanks, but unfortunately that doesn't solve it. I've tried without any
> ~/.emacs and ~/.bashrc, on emacs22, and I still get those initial
> characters. They're not coming from $PS1, so where are they coming from?

PS2? Bash has a whole bunch of env variables for various things,
including one for a
command to run after every line. I'd just do an 'env' and grep through
for anything that
looks like an escape character.

-- 
Alex, homepage: http://www.bennee.com/~alex/
CV: http://www.bennee.com/~alex/cv.php

Re: shell prompt undesired characters

[Dan Davison]

Alex Bennee <kernel-hacker@bennee.com> writes:

> 2009/4/9 Dan Davison <davison@stats.ox.ac.uk>:
>> Thanks, but unfortunately that doesn't solve it. I've tried without any
>> ~/.emacs and ~/.bashrc, on emacs22, and I still get those initial
>> characters. They're not coming from $PS1, so where are they coming from?
>
> PS2? Bash has a whole bunch of env variables for various things,
> including one for a
> command to run after every line. I'd just do an 'env' and grep through
> for anything that
> looks like an escape character.

You're right; that revealed that the answer was $PROMPT_COMMAND. So it
looks like that'll be something to set in ~/.emacs_bash. I should have
looked into this more thoroughly myself... Thanks Peter and Alex for
replies.
Dan