[solved]bash-escape-problem

hungrigerhaifisch · 10-28-2009, 08:01 PM

Hello.
I have the following line in my ~/.bashrc

Code:

PS1='\[\e[0;32m\]\u\[\e[m\] \[\e[1;34m\]\w\[\e[m\] \[\e[m\] \[\e[1;32m\]\$ \[\e[m\]\[\e[1;37m\] '

This is causing commands that 'overflow' a single line to get displayed incorrectly, and it also effects, my bash_history.
I'm guessing that there's a typo in there somewhere, anyone spot it??

Also, I'd like to append the current time (like [02:00]) to the far right of any command I input.

Any quick fixes around?

Thanks

JohnGraham · 10-29-2009, 04:49 AM

Quote:

Originally Posted by hungrigerhaifisch

Hello.
I have the following line in my ~/.bashrc

Code:

PS1='\[\e[0;32m\]\u\[\e[m\] \[\e[1;34m\]\w\[\e[m\] \[\e[m\] \[\e[1;32m\]\$ \[\e[m\]\[\e[1;37m\] '

This is causing commands that 'overflow' a single line to get displayed incorrectly, and it also effects, my bash_history.
I'm guessing that there's a typo in there somewhere, anyone spot it??

Also, I'd like to append the current time (like [02:00]) to the far right of any command I input.

Any quick fixes around?

Thanks

I don't know about the time, but you'll get problems with the prompt if you don't leave "it" with the default colour - i.e. end the prompt with "\[\e[m\]" instead of "\[\e[1;37m\]". If you want the text to be a different colour, there should be a property in your terminal emulator's settings to do that.

John G

hungrigerhaifisch · 10-29-2009, 07:06 AM

Quote:

"\[\e[m\]" instead of "\[\e[1;37m\]"

So simple, thanks, that fixed it!

Anyone know about the time thing? I saw this on some screenshot somewhere, and I'd really like to try it, so if anyone has an idea, I'd be a happy puppy

JohnGraham · 10-29-2009, 07:31 AM

You got me interested now - http://tldp.org/HOWTO/Bash-Prompt-HO...sequences.html

hungrigerhaifisch · 10-29-2009, 10:21 AM

Thanks for the tip.
But I still haven't found out how I can do what I want...

Basically I think I saw something like this:

Code:

user wd $ somecommand                    [current time]

I guess that this would involve somekind of clever scripting, but I'm at a total loss in that area...

EDIT:

I've sadly discovered, that my problem (lines overflowing, this means, when a given line gets to long, it should just wrap around onto the next line, instead it just overwrites my bashpromt) is still there.

Here my line:

Code:

PS1='\[\e[0;32m\]\u\[\e[m\] \[\e[1;34m\]\w\[\e[m\] \[\e[m\] \[\e[1;32m\]\$ \[\e[m\] '

bartonski · 10-29-2009, 05:51 PM

I believe that \t will display time.

Here's my prompt:

Code:

 Thu Oct 29 17:12:15 bchittenden@cribbage:~/bin
>

$PS1 is set to

Code:

\e]0;\h \w\007 \d \t \u@\[\e[1;33m\]\h\[\e[0m\]:\w\n>

I set the color of the hostname according to which drives are mounted: green for pre-production only, yellow for prod and prep, red for production.

"\n> " at the end of the prompt means that I always have an entire line of text to write my commands on... vertical screen real estate isn't as important as getting more of the command on one line.

Oh, by the way, '\e]0;\h \w\007' sets the window title to be my current directory.

bartonski · 10-29-2009, 06:02 PM

Just to make things a little cleaner, I would be inclined to do the following:

Code:

username='\e[0;32m\]\u\[\e[m\]'
wd='\[\e[1;34m\]\w\[\e[m\]'    #wd: working directory
PS1="$username $wd \$ "

Ok, the dollar sign in the prompt doesn't end up green, but otherwise, it's identical, and a lot easier to read in the .bashrc

hungrigerhaifisch · 10-29-2009, 07:22 PM

Nice idea with the variables, makes things a little simpler

BUT: I'm still having this problem with the 'current-line' getting overwritten should the command become too long. This is highly annoying.
Removing any customisation I've done, results in correct behaviour, so there must me something wrong with those lines...

bartonski · 10-29-2009, 11:27 PM

Quote:

Originally Posted by hungrigerhaifisch

Nice idea with the variables, makes things a little simpler

BUT: I'm still having this problem with the 'current-line' getting overwritten should the command become too long. This is highly annoying.
Removing any customisation I've done, results in correct behaviour, so there must me something wrong with those lines...

I set the prompt first to "PS1="$username\$ ", which displayed the problem, then to "$wd \$", which did not.

I went on to split apart '\e[0;32m\]\u\[\e[m\]', and then realized that the reason that I saw the problem is not exactly why you saw the problem:

in

Code:

username='\e[0;32m\]\u\[\e[m\]'

, I left off the initial '\['. The pair of '\[' and \]', as I'm sure that you are aware, causes the contents to be counted as non-printable, i.e. 0 length by bash. If you have these unbalanced, Bash apparently doesn't know what's printable and what's not, causes the length of the string to be mis-calculated. Because it doesn't know how long the string is, it doesn't know where to wrap at the end of the line.

I suspect that you have a much more subtle version of the same error lurking in your prompt somewhere, perhaps a '\[' or '\]' that is being masked by an extra escape character or slash, causing an imbalance which throws off the calculated length of the string.

Check here for more details on non-printable characters in prompts: http://tldp.org/HOWTO/Bash-Prompt-HO...tingchars.html

Cheers, old chum!

http://downhilladventures.com/images...rk%20photo.jpg

hungrigerhaifisch · 10-31-2009, 09:06 AM

Hey, thanks for that!

I think its working now.

It was just missing the '\[' infront of the first '\e' in username

And, I like the picture