Difference between revisions of "Talk:Bash/Prompt customization"

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(Step by step: Improvements?)
(Correct Windows Title Escape Sequence: new section)
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== Return value visualization ==
== Correct Windows Title Escape Sequence ==
The return value visualization stuff didn't quite work right for me.
Currently the listed escape sequence is {{ic|'''ESC''']2;''new title'''''BEL'''}}. But in all links in the "See also" section it is written as {{ic|'''ESC''']0;''new title'''''BEL'''}}, with the number zero (0) instead of the number two (2). Other places I've found on the Internet also uses zero. Which is the correct one?
The command history prints out funny (bits of old command prefixes
-- [[User:Svinto|Svinto]] 09:39, 24 Sep 2018 (UTC)
stay displayed), and also long lines behaved oddly (wrapped back to
start etc.).
I think the trouble maybe coming from echo'ing out color commands
with one echo then putting out the characters to reset the font
elsewhere.  I asked on the bash list and ended up doing this:
    # Make the prompt dark red when the previous command has succeeded, or
    # bright green when it has failed (in keeping with the slightly backwards
    # way exit codes work :).
    red=$(tput setaf 1)
    bright_green=$(tput bold; tput setaf 2)
    reset=$(tput sgr0)
    # Namespace'ed last user command exit status.  We need this I think because
    # the tput commands in the subshells end up resetting $?.
    colors=("$red" "$bright_green")
    PS1='\[${colors[$? != 0]}\]$(if [ $MYPROMPT_LUCES != 0 ]; then \
                                    echo "$MYPROMPT_LUCES "; \
                                fi)\$\[$reset\] '
which displays prompts following successful commands in dark red, and prompts
following failing commands in bright green with the exit code shown.
— Preceding unsigned comment added by [[User:Bkerin|Bkerin]]
There is another, very simple method to get it work without problems with breaking lines.
Rename PS1 to _PS1 in .bashrc and add this lines after _PS1 variable:
    <nowiki>PROMPT_COMMAND='RET=$?; if [[ $RET -eq 0 ]]; then export PS1="${RET_SUCC} ${_PS1}"; else export PS1="${RET_FAIL} ${_PS1}"; fi'</nowiki>
In this example RET_SUCC is <font color="green">✓</font>, and RET_FAIL is <font color="red">✗</font>.
These symbols does not work with text terminal. To fix this, replace first 2 lines with this:
    if [ "$TERM" = "linux" ]
This is only an example, it is possible to add anything that PS1 accepts using this method.
&mdash; Preceding unsigned comment added by [[User:Noctivivans|Noctivivans]]
== Examples ==
This article cries out for examples.  It is tough to tell if one would want to try any of these until one sees an example of what the outcome might be, should it be tried.  I'll bet a lot of people are a little hesitant to try them. - [[User:KitchM|KitchM]] 13:40, 12 April 2010 (EDT)
: I went ahead and added previews of some of the simpler prompts.  As an Archer, you're encouraged to try random stuff just to see what happens.  Don't be hesitant, just have fun! --[[User:DJPohly|DJPohly]] 02:11, 13 April 2010 (EDT)
::Very nice, indeed!  Thank you very much.  This will help immensely.
::This is one Archer that has learned that there is no difference between Arch and any other distro or OS when it comes to the ability to screw things up.  I am very hesitant.  There are so many problems, that I am surprised that people are not having more problems with their systems.  On the other hand, I must assume that people don't use theirs as extensively as do I. In any case, the examples will clearly show a person what happens <u>before</u> they start changing things.  I will dive right in.  I love "zero defects" methods.
::Thanks again.  Keep up the great work. - [[User:KitchM|KitchM]] 16:26, 13 April 2010 (EDT)
I think that the previous one was better, IIRC you can put those things either in .bashrc or bash_profile.
But I'm not sure so I post here and not revert it. Feel free to correct me.
[[User:Karol|Karol]] 05:59, 26 May 2010 (EDT)
== better delete "Advanced return value visualisation" ==
The promt in section "Advanced return value visualisation" cause only problems due wrong length calculation in bash.
$ echo $PS1
$(echo $RET) $(if [[ $RET = 0 ]]; then echo -ne "\[$GREEN\];)"; else echo -ne "\[$RED\];("; fi;) :
this will be expanded to
0 ;) :
But bash think promt is as long as string "$(echo $RET) $(if [[ $RET = 0 ]]; then echo -ne "\[$GREEN\];)"; else echo -ne "\[$RED\];("; fi;) :" and not as long as string " 0 ;) : ". This cause ugly corruption by multi line input.
Quote from here http://www.ibm.com/developerworks/linux/library/l-tip-prompt/:
...In addition to this change, we need to surround
all non-printing characters with special bash escape
sequences, "\[" and "\]". These sequences will tell
bash that the enclosed characters don't take up any
space on the line, which will allow word-wrapping to
continue to work properly. Without them, you'll end
up with a nice-looking prompt that will mess up the
screen if you happen to type in a command that
approaches the extreme right of the terminal. ...
--[[User:Nikel|Nikel]] 18:31, 13 August 2010 (EDT)
== Text entry color ==
I tested output redirection of several types (pipe, redirect, command substitution), and the output of the DEBUG trap was never included. So I simplified the instructions here and removed the hack warning.  If you can give an example that breaks it, leave a comment here saying what it is (because I'm curious!) and go ahead and revert me.  -- [[User:DJPohly|DJPohly]] 13:06, 6 November 2010 (EDT)
== Using Bold and 256 -Color ==
*You can string multiple escape-codes together; This is the only way I could get bold 256-colors to show up on my machine using rxvt-unicode:
  \[\e[(01);(38;5;114)m\]Hello, World
<span style="color: #87d787;font-weight:Bold">Hello, World</span>
Where (01) is the escape for bold and (38;5;114) is the escape for 256-color #114, which is a slight avocado-green.
--[[User:Darkhand|Darkhand]] 15:27, 7 March 2011 (EST)
== Wrong cursorposition ==
After changing all colors from e.g.
my bash stopped missaligning the cursor, clobber old text, and so on.
--[[User:Eselfreund|Eselfreund]] 10:17, 6 August 2011 (EDT)
== bash_completion ==
Currently, it is referred from:
    [ -r /etc/bash_completion ] && . /etc/bash_completion
but Arch seems to install the main script in /usr/share/bash-completion/bash_completion --[[User:Mloskot|Mloskot]] ([[User talk:Mloskot|talk]]) 20:39, 10 June 2012 (UTC)
== Step by step ==
Hello everybody.
I wrote [[Color_Bash_Prompt#A_well-established_Bash_color_prompt|the first chapter]] of this article. I think that [[Color_Bash_Prompt#Step_by_step|the second one (“Step by step”)]] should be improved and harmonized with the first one... I have already given my contribution ;-) Bye --[[User:Martingala|Martingala]] ([[User talk:Martingala|talk]]) 17:59, 15 November 2012 (UTC)

Latest revision as of 09:40, 24 September 2018

Correct Windows Title Escape Sequence

Currently the listed escape sequence is ESC]2;new titleBEL. But in all links in the "See also" section it is written as ESC]0;new titleBEL, with the number zero (0) instead of the number two (2). Other places I've found on the Internet also uses zero. Which is the correct one? -- Svinto 09:39, 24 Sep 2018 (UTC)