# Color Bash Prompt (简体中文)

相关文章

- Environment variables
- Bash

这是一个设置Bash提示符（PS1）色彩以及自定义的参考版本，它可以帮助你在命令行更有效率。您可以添加更多的信息给你的提示符，或者你可以简单地设置的色彩来使提示符中色彩斑斓。

## 一个完善的Bash提示符色彩设置

What follows is a well-proven way to color the Bash prompt. It is the most widespread Bash color scheme in the GNU/Linux world. Here is a preview of how it will appear:

I am two with nature.
-- Woody Allen
andy@alba ~ $ ls
Desktop Documents Music public.desktop
andy@alba ~ $ I\ will\ try\ to\ type\ a\ wrong\ command...
bash: I will try to type a wrong command...: command not found
andy@alba ~ :( $ echo 'Hello world!'
Hello world!
andy@alba su
Password:
Two can Live as Cheaply as One for Half as Long.
-- Howard Kandel
alba ~ $ _

## 安装

这是一个 对于所有用户的方案, 所以你应该开始删除你的 `~/.bashrc` 文件，准备修改`/etc/bash.bashrc` 文件 并且创建一个`/etc/DIR_COLORS` 文件 (或者写在 `~/.bashrc` 和 `/etc/bash.bashrc` 文件中也可以).这里是我们Arch的参考版本(原本这个方案是为Gentoo创建，但这里有一些重要的新增)。

### /etc/bash.bashrc

    # /etc/bash.bashrc
    #
    # https://wiki.archlinux.org/index.php/Color_Bash_Prompt
    #
    # This file is sourced by all *interactive* bash shells on startup,
    # including some apparently interactive shells such as scp and rcp
    # that can't tolerate any output. So make sure this doesn't display
    # anything or bad things will happen !

    # Test for an interactive shell. There is no need to set anything
    # past this point for scp and rcp, and it's important to refrain from
    # outputting anything in those cases.

    # If not running interactively, don't do anything!
    [[ $- != *i* ]] && return

    # Bash won't get SIGWINCH if another process is in the foreground.
    # Enable checkwinsize so that bash will check the terminal size when
    # it regains control.
    # http://cnswww.cns.cwru.edu/~chet/bash/FAQ (E11)
    shopt -s checkwinsize

    # Enable history appending instead of overwriting.
    shopt -s histappend

    case ${TERM} in
    	xterm*|rxvt*|Eterm|aterm|kterm|gnome*)
    		PROMPT_COMMAND=${PROMPT_COMMAND:+$PROMPT_COMMAND; }'printf "\033]0;%s@%s:%s\007" "${USER}" "${HOSTNAME%%.*}" "${PWD/#$HOME/~}"'
    		;;
    	screen)
    		PROMPT_COMMAND=${PROMPT_COMMAND:+$PROMPT_COMMAND; }'printf "\033_%s@%s:%s\033\\" "${USER}" "${HOSTNAME%%.*}" "${PWD/#$HOME/~}"'
    		;;
    esac

    # fortune is a simple program that displays a pseudorandom message
    # from a database of quotations at logon and/or logout.
    # Type: "pacman -S fortune-mod" to install it, then uncomment the
    # following line:

    # [[ "$PS1" ]] && /usr/bin/fortune

    # Set colorful PS1 only on colorful terminals.
    # dircolors --print-database uses its own built-in database
    # instead of using /etc/DIR_COLORS. Try to use the external file
    # first to take advantage of user additions. Use internal bash
    # globbing instead of external grep binary.

    # sanitize TERM:
    safe_term=${TERM//[^[:alnum:]]/?}
    match_lhs=""

    [[ -f ~/.dir_colors ]] && match_lhs="${match_lhs}$(<~/.dir_colors)"
    [[ -f /etc/DIR_COLORS ]] && match_lhs="${match_lhs}$(</etc/DIR_COLORS)"
    [[ -z ${match_lhs} ]] \
    	&& type -P dircolors >/dev/null \
    	&& match_lhs=$(dircolors --print-database)

    if [[ $'\n'${match_lhs} == *$'\n'"TERM "${safe_term}* ]] ; then

    	# we have colors :-)

    	# Enable colors for ls, etc. Prefer ~/.dir_colors
    	if type -P dircolors >/dev/null ; then
    		if [[ -f ~/.dir_colors ]] ; then
    			eval $(dircolors -b ~/.dir_colors)
    		elif [[ -f /etc/DIR_COLORS ]] ; then
    			eval $(dircolors -b /etc/DIR_COLORS)
    		fi
    	fi

    	PS1="$(if [[ ${EUID} == 0 ]]; then echo '\[\033[01;31m\]\h'; else echo '\[\033[01;32m\]\u@\h'; fi)\[\033[01;34m\] \w \$([[ \$? != 0 ]] && echo \"\[\033[01;31m\]:(\[\033[01;34m\] \")\\$\[\033[00m\] "

    	# Use this other PS1 string if you want \W for root and \w for all other users:
    	# PS1="$(if [[ ${EUID} == 0 ]]; then echo '\[\033[01;31m\]\h\[\033[01;34m\] \W'; else echo '\[\033[01;32m\]\u@\h\[\033[01;34m\] \w'; fi) \$([[ \$? != 0 ]] && echo \"\[\033[01;31m\]:(\[\033[01;34m\] \")\\$\[\033[00m\] "

    	alias ls="ls --color=auto"
    	alias dir="dir --color=auto"
    	alias grep="grep --colour=auto"

    else

    	# show root@ when we do not have colors

    	PS1="\u@\h \w \$([[ \$? != 0 ]] && echo \":( \")\$ "

    	# Use this other PS1 string if you want \W for root and \w for all other users:
    	# PS1="\u@\h $(if [[ ${EUID} == 0 ]]; then echo '\W'; else echo '\w'; fi) \$([[ \$? != 0 ]] && echo \":( \")\$ "

    fi

    PS2="> "
    PS3="> "
    PS4="+ "

    # Try to keep environment pollution down, EPA loves us.
    unset safe_term match_lhs

    # Try to enable the auto-completion (type: "pacman -S bash-completion" to install it).
    [ -r /usr/share/bash-completion/bash_completion ] && . /usr/share/bash-completion/bash_completion

    # Try to enable the "Command not found" hook ("pacman -S pkgfile" to install it).
    # See also: https://wiki.archlinux.org/index.php/Bash#The_.22command_not_found.22_hook
    [ -r /usr/share/doc/pkgfile/command-not-found.bash ] && . /usr/share/doc/pkgfile/command-not-found.bash

### /etc/DIR_COLORS

    # Configuration file for the color ls utility
    # This file goes in the /etc directory, and must be world readable.
    # You can copy this file to .dir_colors in your $HOME directory to override
    # the system defaults.

    # COLOR needs one of these arguments: 'tty' colorizes output to ttys, but not
    # pipes. 'all' adds color characters to all output. 'none' shuts colorization
    # off.
    COLOR all

    # Extra command line options for ls go here.
    # Basically these ones are:
    #  -F = show '/' for dirs, '*' for executables, etc.
    #  -T 0 = don't trust tab spacing when formatting ls output.
    OPTIONS -F -T 0

    # Below, there should be one TERM entry for each termtype that is colorizable
    TERM linux
    TERM console
    TERM con132x25
    TERM con132x30
    TERM con132x43
    TERM con132x60
    TERM con80x25
    TERM con80x28
    TERM con80x30
    TERM con80x43
    TERM con80x50
    TERM con80x60
    TERM xterm
    TERM xterm-color
    TERM vt100
    TERM rxvt
    TERM rxvt-256color
    TERM rxvt-cygwin
    TERM rxvt-cygwin-native
    TERM rxvt-unicode
    TERM rxvt-unicode-256color
    TERM rxvt-unicode256
    TERM screen

    # EIGHTBIT, followed by '1' for on, '0' for off. (8-bit output)
    EIGHTBIT 1

    # Below are the color init strings for the basic file types. A color init
    # string consists of one or more of the following numeric codes:
    # Attribute codes:
    # 00=none 01=bold 04=underscore 05=blink 07=reverse 08=concealed
    # Text color codes:
    # 30=black 31=red 32=green 33=yellow 34=blue 35=magenta 36=cyan 37=white
    # Background color codes:
    # 40=black 41=red 42=green 43=yellow 44=blue 45=magenta 46=cyan 47=white
    NORMAL 00	# global default, although everything should be something.
    FILE 00 	# normal file
    DIR 01;34 	# directory
    LINK 01;36 	# symbolic link
    FIFO 40;33	# pipe
    SOCK 01;35	# socket
    BLK 40;33;01	# block device driver
    CHR 40;33;01 	# character device driver

    # This is for files with execute permission:
    EXEC 01;32

    # List any file extensions like '.gz' or '.tar' that you would like ls
    # to colorize below. Put the extension, a space, and the color init string.
    # (and any comments you want to add after a '#')
    .cmd 01;32 # executables (bright green)
    .exe 01;32
    .com 01;32
    .btm 01;32
    .bat 01;32
    .tar 01;31 # archives or compressed (bright red)
    .tgz 01;31
    .arj 01;31
    .taz 01;31
    .lzh 01;31
    .zip 01;31
    .z   01;31
    .Z   01;31
    .gz  01;31
    .jpg 01;35 # image formats
    .gif 01;35
    .bmp 01;35
    .xbm 01;35
    .xpm 01;35
    .tif 01;35

### /etc/skel/

这篇技巧告诉你如何使用`/etc/skel/`目录，以确保所有新用户在您的系统上获得相同的初始设置。

`/etc/skel/` 目录是使用`useradd` 创建一个新用户时里面的文件会复制新建用户的home目录下。

要修改`/etc/skel/`这个路径,可以编辑`/etc/default/useradd`文件.

    # useradd defaults file
    GROUP=100
    HOME=/home
    INACTIVE=-1
    EXPIRE=
    SHELL=/bin/bash
    SKEL=/etc/skel

通常`/etc/skel/` 包含一些`.rc` 文件用于shell初始化, 但是你也可以添加一个`public_html`目录, 一个`.dir_colors`文件,或者是其他的东西.

andy@alba /etc/skel $ ls -A
.bash_logout .bash_profile .bashrc .xinitrc .xsession
andy@alba /etc/skel $ _

更多关于`/etc/skel/`目录自定义的信息, 输入: `$ man useradd`。 看也可以: http://www.gentoo.org/news/en/gwn/20031222-newsletter.xml.

现在，在`/etc/skel/.bashrc` 目录中的文件`.bashrc` 已经复制到每个新用户的主目录中了它会看起来像这样：

    #
    # ~/.bashrc
    #

    # If not running interactively, don't do anything
    [[ $- != *i* ]] && return

    alias ls='ls --color=auto'
    PS1='[\u@\h \W]\$ '

As you can see, a `PS1` variable (i.e.: the prompt) is exported. So, if you had previously created a color prompt through the `/etc/bash.bashrc` file, each user newly created, to see it, should delete the line

    PS1='[\u@\h \W]\$ '

from his own `~/.bashrc`. Accordingly, if you want to grant to newly created users to have the same colorfull `PS1`, you should delete that line from `/etc/skel/.bashrc`.

## Example of cohabitation of /etc/bash.bashrc and ~/.bashrc

`~/.bashrc` and `/etc/bash.bashrc` can also cohabitate. Here is a possible example of a typical Arch user's `~/.bashrc` file which can cohabit with the `/etc/bash.bashrc` file proposed here, valid for all users. The output will remain coloured.

    #
    # ~/.bashrc
    #

    # If not running interactively, don't do anything
    [[ $- != *i* ]] && return

    # pacman/yaourt aliases
    alias pac="sudo /usr/bin/pacman -S"		# default action	- install one or more packages
    alias paca="/usr/bin/yaourt -S"			# default yaourt action	- install one or more packages including AUR
    alias pacu="/usr/bin/yaourt -Syua"		# '[u]pdate'		- upgrade all packages to their newest version
    alias pacr="sudo /usr/bin/yaourt -Rs"		# '[r]emove'		- uninstall one or more packages
    alias pacs="/usr/bin/pacman -Ss"		# '[s]earch'		- search for a package using one or more keywords
    alias pacys="/usr/bin/yaourt -Ss"		# '[y]aourt [s]earch'	- search for a package or a PKGBUILD using one or more keywords
    alias paci="/usr/bin/yaourt -Si"		# '[i]nfo'		- show information about a package
    alias paclo="/usr/bin/pacman -Qdt"		# '[l]ist [o]rphans'	- list all packages which are orphaned
    alias pacc="sudo /usr/bin/pacman -Scc"		# '[c]lean cache'	- delete all not currently installed package files
    alias paclf="/usr/bin/pacman -Ql"		# '[l]ist [f]iles'	- list all files installed by a given package
    alias pacexpl="/usr/bin/yaourt -D --asexplicit"	# 'mark as [expl]icit'	- mark one or more packages as explicitly installed
    alias pacimpl="/usr/bin/yaourt -D --asdeps"	# 'mark as [impl]icit'	- mark one or more packages as non explicitly installed

    # '[r]emove [o]rphans' - recursively remove ALL orphaned packages
    alias pacro="/usr/bin/pacman -Qtdq > /dev/null && sudo /usr/bin/pacman -Rs \$(/usr/bin/pacman -Qtdq | sed -e ':a;N;$!ba;s/\n/ /g')"

## Random quotations at logon

If you want a random quotation at logon (like Slackware) you must install Fortune. Fortune is a simple program that displays a pseudorandom message from a database of quotations at logon and/or logout. Type `pacman -S fortune-mod` to install it, then uncomment the following line from our `/etc/bash.bashrc` file:

    # [[ "$PS1" ]] && /usr/bin/fortune

If you want to colorize (brown in this example) the random message from fortune, replace the previous commented text with:

    [[ "$PS1" ]] && echo -e "\e[00;33m$(/usr/bin/fortune)\e[00m"

## Colorized Arch latest news at logon

If you want to read the latest news from the Arch Official Website, instead of a random quotation from fortune, replace the following lines from our `/etc/bash.bashrc` file:

    # fortune is a simple program that displays a pseudorandom message
    # from a database of quotations at logon and/or logout.
    # Type: "pacman -S fortune-mod" to install it, then uncomment the
    # following line:

    # [[ "$PS1" ]] && /usr/bin/fortune

with:

    # Arch latest news

    if [ "$PS1" ]; then
    	# The characters "£, §" are used as metacharacters. They should not be encountered in a feed...
    	echo -e "$(echo $(curl --silent https://www.archlinux.org/feeds/news/ | sed -e ':a;N;$!ba;s/\n/ /g') | \
    		sed -e 's/&amp;/\&/g
    		s/&lt;\|&#60;/</g
    		s/&gt;\|&#62;/>/g
    		s/<\/a>/£/g
    		s/href\=\"/§/g
    		s/<title>/\\n\\n\\n   :: \\e[01;31m/g; s/<\/title>/\\e[00m ::\\n/g
    		s/<link>/ [ \\e[01;36m/g; s/<\/link>/\\e[00m ]/g
    		s/<description>/\\n\\n\\e[00;37m/g; s/<\/description>/\\e[00m\\n\\n/g
    		s/<p\( [^>]*\)\?>\|<br\s*\/\?>/\n/g
    		s/<b\( [^>]*\)\?>\|<strong\( [^>]*\)\?>/\\e[01;30m/g; s/<\/b>\|<\/strong>/\\e[00;37m/g
    		s/<i\( [^>]*\)\?>\|<em\( [^>]*\)\?>/\\e[41;37m/g; s/<\/i>\|<\/em>/\\e[00;37m/g
    		s/<u\( [^>]*\)\?>/\\e[4;37m/g; s/<\/u>/\\e[00;37m/g
    		s/<code\( [^>]*\)\?>/\\e[00m/g; s/<\/code>/\\e[00;37m/g
    		s/<a[^§|t]*§\([^\"]*\)\"[^>]*>\([^£]*\)[^£]*£/\\e[01;31m\2\\e[00;37m \\e[01;34m[\\e[00;37m \\e[04m\1\\e[00;37m\\e[01;34m ]\\e[00;37m/g
    		s/<li\( [^>]*\)\?>/\n \\e[01;34m*\\e[00;37m /g
    		s/<!\[CDATA\[\|\]\]>//g
    		s/\|>\s*<//g
    		s/ *<[^>]\+> */ /g
    		s/[<>£§]//g')\n\n";
    fi

that is a small and coloured RSS escaping script written by the user grufo which will display an output like this:

:: Arch Linux: Recent news updates ::
[ https://www.archlinux.org/news/ ]
The latest and greatest news from the Arch Linux distribution.
en-us Sun, 04 Nov 2012 16:09:46 +0000
:: End of initscripts support ::
[ https://www.archlinux.org/news/end-of-initscripts-support/ ]
Tom Gundersen wrote:
As systemd is now the default init system, Arch Linux is receiving minimal testing on initscripts systems. Due to a lack of resources and interest, we are unlikely to work on fixing initscripts-specific bugs, and may close them as WONTFIX.
We therefore strongly encourage all users to migrate to systemd as soon as possible. See the systemd migration guide [ https://wiki.archlinux.org/index.php/Systemd ].
To ease the transition, initscripts support will remain in the official repositories for the time being, unless otherwise stated. As of January 2013, we will start removing initscripts support (e.g., rc scripts) from individual packages without further notice.
Tom Gundersen Sun, 04 Nov 2012 16:09:46 +0000 tag:www.archlinux.org,2012-11-04:/news/end-of-initscripts-support/
:: November release of install media available ::
[ https://www.archlinux.org/news/november-release-of-install-media-available/ ]
Pierre Schmitz wrote:
The latest snapshot of our install and rescue media can be found on our Download [ https://www.archlinux.org/download/ ] page. The 2012.11.01 ISO image mainly contains minor bug fixes, cleanups and new packages compared to the previous one:
* First media with Linux 3.6
* copytoram=n can be used to not copy the image to RAM on network boot. This is probably unreliable but an option for systems with very low memory.
* cowfile_size boot parameter mainly for persistent COW on VFAT. See the README [ https://projects.archlinux.org/archiso.git/plain/docs/README.bootparams?id=v4 ] file for details.
Pierre Schmitz Fri, 02 Nov 2012 17:54:15 +0000 tag:www.archlinux.org,2012-11-02:/news/november-release-of-install-media-available/
:: Bug Squashing Day: Saturday 17th November ::
[ https://www.archlinux.org/news/bug-squashing-day-saturday-17th-november/ ]
Allan McRae wrote:
The number of bugs in the Arch Linux bug tracker is creeping up so it is time for some extermination.
This is a great way for the community to get involved and help the Arch Linux team. The process is simple. First look at a bug for your favorite piece of software in the bug tracker and check if it still occurs. If it does, check the upstream project for a fix and test it to confirm it works. If there is no fix available, make sure the bug has been filed in the upstream tracker.
Join us on the #archlinux-bugs IRC channel. We are spread across timezones, so people should be around all day.
Allan McRae Thu, 01 Nov 2012 12:28:51 +0000 tag:www.archlinux.org,2012-11-01:/news/bug-squashing-day-saturday-17th-november/
:: ConsoleKit replaced by logind ::
[ https://www.archlinux.org/news/consolekit-replaced-by-logind/ ]
Allan McRae wrote:
With GNOME 3.6, polkit and networkmanager moving to [extra], ConsoleKit has now been removed from the repositories. Any package that previously depended on it now relies on systemd-logind instead. That means that the system must be booted with systemd to be fully functional.
In addition to GNOME, both KDE and XFCE are also affected by this change.
Allan McRae Tue, 30 Oct 2012 22:17:39 +0000 tag:www.archlinux.org,2012-10-30:/news/consolekit-replaced-by-logind/
:: systemd is now the default on new installations ::
[ https://www.archlinux.org/news/systemd-is-now-the-default-on-new-installations/ ]
Thomas Bächler wrote:
The base group now contains the systemd-sysvcompat package. This means that all new installations will boot with systemd by default.
As some packages still lack native systemd units, users can install the initscripts package and use the DAEMONS array in /etc/rc.conf to start services using the legacy rc.d scripts.
This change does not affect existing installations. For the time being, the initscripts and sysvinit packages remain available from our repositories. However, individual packages may now start relying on the system being booted with systemd.
Please refer to the wiki [ https://wiki.archlinux.org/index.php/Systemd ] for how to transition an existing installation to systemd.
Thomas Bächler Sat, 13 Oct 2012 09:29:38 +0000 tag:www.archlinux.org,2012-10-13:/news/systemd-is-now-the-default-on-new-installations/
:: Install medium 2012.10.06 introduces systemd ::
[ https://www.archlinux.org/news/install-medium-20121006-introduces-systemd/ ]
Pierre Schmitz wrote:
The October release of the Arch Linux install medium is available for Download [ https://www.archlinux.org/download/ ] and can be used for new installs or as a rescue system. It contains a set of updated packages and the following notable changes:
* systemd is used to boot up the live system.
* initscripts are no longer available on the live system but are still installed by default on the target system. This is likely to change in the near future.
* EFI boot and setup has been simplified.
* gummiboot is used to display a menu on EFI systems.
* The following new packages are available on the live system: ethtool, fsarchiver, gummiboot-efi, mc, partclone, partimage, refind-efi, rfkill, sudo, testdisk, wget, xl2tpd
Pierre Schmitz Sun, 07 Oct 2012 16:58:03 +0000 tag:www.archlinux.org,2012-10-07:/news/install-medium-20121006-introduces-systemd/
:: New install medium 2012.09.07 ::
[ https://www.archlinux.org/news/new-install-medium-20120907/ ]
Pierre Schmitz wrote:
As is customary by now there is a new install medium available at the beginning of this month. The live system can be downloaded from Download [ https://www.archlinux.org/download/ ] and be used for new installs or as a rescue system.
In addition to a couple of updated packages and bug fixes the following changes stand out:
* First medium with Linux 3.5 (3.5.3)
* The script boot parameter works again (FS#31022 [ https://bugs.archlinux.org/task/31022 ])
* When booting via PXE and NFS or NBD the ISO will be copied to RAM to ensure a more stable usage.
* The live medium contains usb_modeswitch and wvdial which e.g. allows to establish a network connection using an UMTS USB dongle
* Furthermore the newest versions of initscripts, systemd and netcfg are included.
Pierre Schmitz Sat, 08 Sep 2012 09:48:52 +0000 tag:www.archlinux.org,2012-09-08:/news/new-install-medium-20120907/
:: Fontconfig 2.10.1 update - manual intervention required ::
[ https://www.archlinux.org/news/fontconfig-2101-update-manual-intervention-required/ ]
Andreas Radke wrote:
The fontconfig 2.10.1 update overwrites symlinks created by the former package version. These symlinks need to be removed before the update:
rm /etc/fonts/conf.d/20-unhint-small-vera.conf
rm /etc/fonts/conf.d/20-fix-globaladvance.conf
rm /etc/fonts/conf.d/29-replace-bitmap-fonts.conf
rm /etc/fonts/conf.d/30-metric-aliases.conf
rm /etc/fonts/conf.d/30-urw-aliases.conf
rm /etc/fonts/conf.d/40-nonlatin.conf
rm /etc/fonts/conf.d/45-latin.conf
rm /etc/fonts/conf.d/49-sansserif.conf
rm /etc/fonts/conf.d/50-user.conf
rm /etc/fonts/conf.d/51-local.conf
rm /etc/fonts/conf.d/60-latin.conf
rm /etc/fonts/conf.d/65-fonts-persian.conf
rm /etc/fonts/conf.d/65-nonlatin.conf
rm /etc/fonts/conf.d/69-unifont.conf
rm /etc/fonts/conf.d/80-delicious.conf
rm /etc/fonts/conf.d/90-synthetic.conf
pacman -Sy fontconfig
Main systemwide configuration should be done by symlinks (especially for autohinting, sub-pixel and lcdfilter):
cd /etc/fonts/conf.d
ln -s ../conf.avail/XX-foo.conf
Also check Font Configuration [ https://wiki.archlinux.org/index.php/Font_Configuration ] and Fonts [ https://wiki.archlinux.org/index.php/Fonts ].
Andreas Radke Thu, 06 Sep 2012 13:54:23 +0000 tag:www.archlinux.org,2012-09-06:/news/fontconfig-2101-update-manual-intervention-required/
:: netcfg-2.8.9 drops deprecated rc.conf compatibility ::
[ https://www.archlinux.org/news/netcfg-289-drops-initscripts-compatibility/ ]
Florian Pritz wrote:
Users of netcfg should configure all interfaces in /etc/conf.d/netcfg rather than /etc/rc.conf.
Florian Pritz Sat, 11 Aug 2012 20:00:02 +0000 tag:www.archlinux.org,2012-08-11:/news/netcfg-289-drops-initscripts-compatibility/
:: Install media 2012.08.04 available ::
[ https://www.archlinux.org/news/install-media-20120804-available/ ]
Pierre Schmitz wrote:
The August snapshot of our live and install media comes with updated packages and the following changes on top of the previous ISO image [ /news/install-media-20120715-released/ ]:
* GRUB 2.0 instead of the legacy 0.9 version is available.
* The Installation Guide [ https://wiki.archlinux.org/index.php/Installation_Guide ] can be found at /root/install.txt.
* ZSH with Grml's configuration [ http://grml.org/zsh/ ] is used as interactive shell to provide a user friendly and more convenient environment. This includes completion support for pacstrap, arch-chroot, pacman and most other tools.
* The network daemon is started by default which will automatically setup your network if DHCP is available.
Note that all these changes only affect the live system and not the base system you install using pacstrap. The ISO image can be downloaded from our download page [ /download/ ]. The next snapshot is scheduled for September.
Pierre Schmitz Sat, 04 Aug 2012 17:24:30 +0000 tag:www.archlinux.org,2012-08-04:/news/install-media-20120804-available/
andy@alba _

If you don't want to see months worth of updates but only the latest item, you can use this::

    # Arch latest news

    if [ "$PS1" ]; then
    	# The characters "£, §" are used as metacharacters. They should not be encountered in a feed...
    	echo -e "$(echo $(curl --silent https://www.archlinux.org/feeds/news/ | awk ' NR == 1 {while ($0 !~ /<\/item>/) {print;getline} sub(/<\/item>.*/,"</item>") ;print}' | sed -e ':a;N;$!ba;s/\n/ /g') | \
    		sed -e 's/&amp;/\&/g
    		s/&lt;\|&#60;/</g
    		s/&gt;\|&#62;/>/g
    		s/<\/a>/£/g
    		s/href\=\"/§/g
    		s/<title>/\\n\\n\\n   :: \\e[01;31m/g; s/<\/title>/\\e[00m ::\\n/g
    		s/<link>/ [ \\e[01;36m/g; s/<\/link>/\\e[00m ]/g
    		s/<description>/\\n\\n\\e[00;37m/g; s/<\/description>/\\e[00m\\n\\n/g
    		s/<p\( [^>]*\)\?>\|<br\s*\/\?>/\n/g
    		s/<b\( [^>]*\)\?>\|<strong\( [^>]*\)\?>/\\e[01;30m/g; s/<\/b>\|<\/strong>/\\e[00;37m/g
    		s/<i\( [^>]*\)\?>\|<em\( [^>]*\)\?>/\\e[41;37m/g; s/<\/i>\|<\/em>/\\e[00;37m/g
    		s/<u\( [^>]*\)\?>/\\e[4;37m/g; s/<\/u>/\\e[00;37m/g
    		s/<code\( [^>]*\)\?>/\\e[00m/g; s/<\/code>/\\e[00;37m/g
    		s/<a[^§|t]*§\([^\"]*\)\"[^>]*>\([^£]*\)[^£]*£/\\e[01;31m\2\\e[00;37m \\e[01;34m[\\e[00;37m \\e[04m\1\\e[00;37m\\e[01;34m ]\\e[00;37m/g
    		s/<li\( [^>]*\)\?>/\n \\e[01;34m*\\e[00;37m /g
    		s/<!\[CDATA\[\|\]\]>//g
    		s/\|>\s*<//g
    		s/ *<[^>]\+> */ /g
    		s/[<>£§]//g')\n\n";
    fi

See this thread for details.

## Variations on a theme

Here are some `PS1` variables (i.e.: prompts) with different layout to be applyied to our `/etc/bash.bashrc` file. When you choose a layout you must replace the following lines from our `/etc/bash.bashrc` file:

    	PS1="$(if [[ ${EUID} == 0 ]]; then echo '\[\033[01;31m\]\h'; else echo '\[\033[01;32m\]\u@\h'; fi)\[\033[01;34m\] \w \$([[ \$? != 0 ]] && echo \"\[\033[01;31m\]:(\[\033[01;34m\] \")\$\[\033[00m\] "

    	# Use this other PS1 string if you want \W for root and \w for all other users:
    	# PS1="$(if [[ ${EUID} == 0 ]]; then echo '\[\033[01;31m\]\h\[\033[01;34m\] \W'; else echo '\[\033[01;32m\]\u@\h\[\033[01;34m\] \w'; fi) \$([[ \$? != 0 ]] && echo \"\[\033[01;31m\]:(\[\033[01;34m\] \")\$\[\033[00m\] "

with the `PS1` variable (and possibly other code lines) given by the choosen layout.

### From Arch Forum #1

Here is an unicode variation of our `/etc/bash.bashrc` file freely based on what wrote the user JeSuisNerd and others in the Arch Forum. Here is a preview of how it will appear:

I am two with nature.
-- Woody Allen
┌─[andy@alba]─[~]
└──╼ ls
Desktop Documents Music public.desktop
┌─[andy@alba]─[~]
└──╼ I\ will\ try\ to\ type\ a\ wrong\ command...
bash: I will try to type a wrong command...: command not found
┌─[✗]─[andy@alba]─[~]
└──╼ echo 'Hello world!' Hello world!
┌─[andy@alba]─[~]
└──╼ su
Password:
Two can Live as Cheaply as One for Half as Long.
-- Howard Kandel
┌─[alba]─[~]
└──╼ _

Note: Some unicode symbols (like ✗ and ╼) are not well supported in some terminals (in linux console, for example), so this prompt will appear a bit different depending on where is displayed. If you want to know the unicode representation of a plain text, here you have a little plain text converter.

And finally here is the `PS1` variable for this effect to be applyied to our `/etc/bash.bashrc` file (see above):

    	# https://bbs.archlinux.org/viewtopic.php?pid=1068202#p1068202
    	PS1="\[\033[0;37m\]\342\224\214\342\224\200\$([[ \$? != 0 ]] && echo \"[\[\033[0;31m\]\342\234\227\[\033[0;37m\]]\342\224\200\")[$(if [[ ${EUID} == 0 ]]; then echo '\[\033[0;31m\]\h'; else echo '\[\033[0;33m\]\u\[\033[0;37m\]@\[\033[0;96m\]\h'; fi)\[\033[0;37m\]]\342\224\200[\[\033[0;32m\]\w\[\033[0;37m\]]\n\[\033[0;37m\]\342\224\224\342\224\200\342\224\200\342\225\274 \[\033[0m\]"

### From an italian blog…

Here is an unicode variation of our `/etc/bash.bashrc` file freely based on an italian blog. Here is a preview of how it will appear:

I am two with nature.
-- Woody Allen
┌─[12:03:20]─[andy@alba]
└──> ~ $ ls
Desktop Documents Music public.desktop
┌─[12:03:31]─[andy@alba]
└──> ~ $ I\ will\ try\ to\ type\ a\ wrong\ command...
bash: I will try to type a wrong command...: command not found
┌─[✗]─[12:04:01]─[andy@alba]
└──> ~ $ echo 'Hello world!'
Hello world!
┌─[12:04:13]─[andy@alba]
└──> ~ $ su
Password:
Two can Live as Cheaply as One for Half as Long.
-- Howard Kandel
┌─[12:04:21]─[root@alba]
└──> ~ $ _

Note: Some unicode symbols (like ✗) are not well supported in some terminals (in linux console, for example), so this prompt will appear a bit different depending on where is displayed. If you want to know the unicode representation of a plain text, here you have a little plain text converter.

And finally here is the `PS1` variable for this effect to be applyied to our `/etc/bash.bashrc` file (see above):

    	if [[ ${EUID} == 0 ]] ; then
    		sq_color="\[\033[0;31m\]"
    	else
    		sq_color="\[\033[0;34m\]"
    	fi

    	PS1="$sq_color\342\224\214\342\224\200\$([[ \$? != 0 ]] && echo \"[\[\033[01;37m\]\342\234\227$sq_color]\342\224\200\")[\[\033[01;37m\]\t$sq_color]\342\224\200[\[\033[01;37m\]\u@\h$sq_color]\n\342\224\224\342\224\200\342\224\200> \[\033[01;37m\]\W$sq_color $ \[\033[01;37m\]>>\\[\\033[0m\\] "

    	unset sq_color

### From Arch Forum #2

Here is another variation of our `/etc/bash.bashrc` file freely based on what wrote the user shumer1213 and others in the Arch Forum. Here is a preview of how it will appear:

I am two with nature.
-- Woody Allen
██ [ ~ ] [ 18:05:58 ]
██ ls
Desktop Documents Music public.desktop
██ [ ~ ] [ 18:06:02 ]
██ I\ will\ try\ to\ type\ a\ wrong\ command...
bash: I will try to type a wrong command...: command not found
██ [ ~ ] [ 18:06:12 ]
██ echo 'Hello world!'
Hello world!
██ [ ~ ] [ 18:06:17 ]
██ su
Password:
Two can Live as Cheaply as One for Half as Long.
-- Howard Kandel
██ [ andy ] [ 18:06:26 ]
██ _

Here is the `PS1` variable for this effect to be applyied to our `/etc/bash.bashrc` file (see above):

    	# https://bbs.archlinux.org/viewtopic.php?pid=1156660#p1156660
    	PS1="\n\$(if [[ \$? == 0 ]]; then echo \"\[\033[0;34m\]\"; else echo \"\[\033[0;31m\]\"; fi)\342\226\210\342\226\210 [ \W ] [ \t ]\n\[\033[0m\]\342\226\210\342\226\210 "

### With directory information

Here are other three variations of our `/etc/bash.bashrc` file freely based on the article 8 Useful and Interesting Bash Prompts. Here is a preview of how they will appear:

#### Version #1: with numerical error

I am two with nature.
-- Woody Allen
┌(andy@alba)─(0)─(02:38 PM Sat Aug 29)
└─(~)─(4 files, 332Kb)─> ls
Desktop Documents Music myScript.js
┌(andy@alba)─(0)─(02:38 PM Sat Aug 29)
└─(~)─(4 files, 332Kb)─> I\ will\ try\ to\ type\ a\ wrong\ command...
bash: I will try to type a wrong command...: command not found
┌(andy@alba)─(127)─(02:39 PM Sat Aug 29)
└─(~)─(4 files, 332Kb)─> echo 'Hello world!'
Hello world!
┌(andy@alba)─(0)─(02:39 PM Sat Aug 29)
└─(~)─(4 files, 332Kb)─> false
┌(andy@alba)─(1)─(02:39 PM Sat Aug 29)
└─(~)─(4 files, 332Kb)─> su
Password:
Two can Live as Cheaply as One for Half as Long.
-- Howard Kandel
┌(alba)─(0)─(02:39 PM Sat Aug 29)
└─(/home/andy)─(4 files, 332Kb)─> _

Here is the `PS1` variable for this effect to be applyied to our `/etc/bash.bashrc` file (see above):

    	# http://maketecheasier.com/8-useful-and-interesting-bash-prompts/2009/09/04
    	PS1="\n\[\033[1;37m\]\342\224\214($(if [[ ${EUID} == 0 ]]; then echo '\[\033[01;31m\]\h'; else echo '\[\033[01;34m\]\u@\h'; fi)\[\033[1;37m\])\342\224\200(\[\033[1;34m\]\$?\[\033[1;37m\])\342\224\200(\[\033[1;34m\]\@ \d\[\033[1;37m\])\[\033[1;37m\]\n\342\224\224\342\224\200(\[\033[1;32m\]\w\[\033[1;37m\])\342\224\200(\[\033[1;32m\]\$(ls -1 | wc -l | sed 's: ::g') files, \$(ls -lah | grep -m 1 total | sed 's/total //')b\[\033[1;37m\])\342\224\200> \[\033[0m\]"

#### Version #2: with unicode error status symbols

I am two with nature.
-- Woody Allen
┌(andy@alba)─(✓)─(02:38 PM Sat Aug 29)
└─(~)─(4 files, 332Kb)─> ls
Desktop Documents Music myScript.js
┌(andy@alba)─(✓)─(02:38 PM Sat Aug 29)
└─(~)─(4 files, 332Kb)─> I\ will\ try\ to\ type\ a\ wrong\ command...
bash: I will try to type a wrong command...: command not found
┌(andy@alba)─(✗)─(02:39 PM Sat Aug 29)
└─(~)─(4 files, 332Kb)─> echo 'Hello world!'
Hello world!
┌(andy@alba)─(✓)─(02:39 PM Sat Aug 29)
└─(~)─(4 files, 332Kb)─> false
┌(andy@alba)─(✗)─(02:39 PM Sat Aug 29)
└─(~)─(4 files, 332Kb)─> su
Password:
Two can Live as Cheaply as One for Half as Long.
-- Howard Kandel
┌(alba)─(✓)─(02:39 PM Sat Aug 29)
└─(/home/andy)─(4 files, 332Kb)─> _

Here is the `PS1` variable for this effect to be applyied to our `/etc/bash.bashrc` file (see above):

    	# http://maketecheasier.com/8-useful-and-interesting-bash-prompts/2009/09/04
    	PS1="\n\[\033[1;37m\]\342\224\214($(if [[ ${EUID} == 0 ]]; then echo '\[\033[01;31m\]\h'; else echo '\[\033[01;34m\]\u@\h'; fi)\[\033[1;37m\])\342\224\200(\$(if [[ \$? == 0 ]]; then echo \"\[\033[01;32m\]\342\234\223\"; else echo \"\[\033[01;31m\]\342\234\227\"; fi)\[\033[1;37m\])\342\224\200(\[\033[1;34m\]\@ \d\[\033[1;37m\])\[\033[1;37m\]\n\342\224\224\342\224\200(\[\033[1;32m\]\w\[\033[1;37m\])\342\224\200(\[\033[1;32m\]\$(ls -1 | wc -l | sed 's: ::g') files, \$(ls -lah | grep -m 1 total | sed 's/total //')b\[\033[1;37m\])\342\224\200> \[\033[0m\]"

#### Version #3: with unicode error status symbol (non-zero only)

I am two with nature.
-- Woody Allen
┌(andy@alba)─(02:38 PM Sat Aug 29)
└─(~)─(4 files, 332Kb)─> ls
Desktop Documents Music myScript.js
┌(andy@alba)─(02:38 PM Sat Aug 29)
└─(~)─(4 files, 332Kb)─> I\ will\ try\ to\ type\ a\ wrong\ command...
bash: I will try to type a wrong command...: command not found
┌(andy@alba)─(✗)─(02:39 PM Sat Aug 29)
└─(~)─(4 files, 332Kb)─> echo 'Hello world!'
Hello world!
┌(andy@alba)─(02:39 PM Sat Aug 29)
└─(~)─(4 files, 332Kb)─> false
┌(andy@alba)─(✗)─(02:39 PM Sat Aug 29)
└─(~)─(4 files, 332Kb)─> su
Password:
Two can Live as Cheaply as One for Half as Long.
-- Howard Kandel
┌(alba)─(02:39 PM Sat Aug 29)
└─(/home/andy)─(4 files, 332Kb)─> _

Here is the `PS1` variable for this effect to be applyied to our `/etc/bash.bashrc` file (see above):

    	# http://maketecheasier.com/8-useful-and-interesting-bash-prompts/2009/09/04
    	PS1="\n\[\033[1;37m\]\342\224\214($(if [[ ${EUID} == 0 ]]; then echo '\[\033[01;31m\]\h'; else echo '\[\033[01;34m\]\u@\h'; fi)\[\033[1;37m\])\$([[ \$? != 0 ]] && echo \"\342\224\200(\[\033[0;31m\]\342\234\227\[\033[1;37m\])\")\342\224\200(\[\033[1;34m\]\@ \d\[\033[1;37m\])\[\033[1;37m\]\n\342\224\224\342\224\200(\[\033[1;32m\]\w\[\033[1;37m\])\342\224\200(\[\033[1;32m\]\$(ls -1 | wc -l | sed 's: ::g') files, \$(ls -lah | grep -m 1 total | sed 's/total //')b\[\033[1;37m\])\342\224\200> \[\033[0m\]"

## Restoring the original /etc/bash.bashrc file

If you repent having modified the `/etc/bash.bashrc` file, you can always restore the original Arch `/etc/bash.bashrc` file from the bash package and remove the `/etc/DIR_COLORS` file. Note that there is not an "official" bash.bashrc: each distribution has its own.

## Original /etc/bash.bashrc from Gentoo

The original not modified Gentoo's `/etc/bash.bashrc` file can be found here.

# Step by step

If you want to create a style all your own, you can take a look at these tips. This Forum thread could give you more informations and examples.

## Basic prompts

The following settings are useful for distinguishing the root prompt from non-root users.

- Edit Bash's personal configuration file:

    $ nano ~/.bashrc

- Comment out the default prompt:

    # PS1='[\u@\h \W]\$ '

- Add the following green prompt for regular users:

[chiri@zetsubou ~]$ _

    PS1='\[\e[1;32m\][\u@\h \W]\$\[\e[0m\] '

- Edit root's .bashrc file; copy it from /etc/skel if the file is not present:

    $ nano /root/.bashrc

- Assign a red prompt for root:

[root@zetsubou ~]# _

    PS1='\[\e[1;31m\][\u@\h \W]\$\[\e[0m\] '

### Slightly fancier prompts

- A green and blue prompt for regular users:

chiri ~/docs $ echo "sample output text"
sample output text
chiri ~/docs $ _

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

This will give a very pleasing, colorful prompt and theme for the console with bright white text.

The string above contains color-set escape sequences (start coloring: \[\e[color\], end coloring: \[\e[m\]) and information placeholders:

- \u - Username. The original prompt also has \h, which prints the host name.
- \w - Current absolute path. Use \W for current relative path.
- \$ - The prompt character (eg. '#' for root, '$' for regular users).

The last color-set sequence, "\[\e[1;37m\]", is not closed, so the remaining text (everything typed into the terminal, program output and so on) will be in that (bright white) color. It may be desirable to change this color, or to delete the last escape sequence in order to leave the actual output in unaltered color.

- A red and blue prompt for root:

root ~/docs # echo "sample output text"
sample output text
root ~/docs # _

    PS1='\[\e[0;31m\]\u\[\e[m\] \[\e[1;34m\]\w\[\e[m\] \[\e[0;31m\]\$ \[\e[m\]\[\e[0;32m\]'

This will give you a red designation and green console text.

Once you have made your changes to .bashrc, to execute your changes:

    $ source ~/.bashrc

## Advanced prompts

### Load/Mem Status for 256colors

This is not even pushing the limits. Other than using 'sed' to parse the memory and load average (using the -u option for non-buffering), and the builtin history to save your history to your HISTFILE after every command, which you may find incredibly useful when dealing with crashing shells or subshells, this is essentially just making BASH print variables it already knows, making this extremely fast compared to prompts with non-builtin commands.

This prompt is from AskApache.com's BASH Power Prompt article, which goes into greater detail. It is especially helpful for those wanting to understand 256 color terminals, ncurses, termcap, and terminfo.

This is for 256 color terminals, which is where the \033[38;5;22m terminal escapes come from.

    802/1024MB      1.28 1.20 1.13 3/94 18563
    [5416:17880 0:70] 05:35:50 Wed Apr 21 [srot@host.sqpt.net:/dev/pts/0 +1] ~

    (1:70)$ _

    PROMPT_COMMAND='history -a;echo -en "\033[m\033[38;5;2m"$(( `sed -nu "s/MemFree:[\t ]\+\([0-9]\+\) kB/\1/p" /proc/meminfo`/1024))"\033[38;5;22m/"$((`sed -nu "s/MemTotal:[\t ]\+\([0-9]\+\) kB/\1/Ip" /proc/meminfo`/1024 ))MB"\t\033[m\033[38;5;55m$(< /proc/loadavg)\033[m"'
    PS1='\[\e[m\n\e[1;30m\][$$:$PPID \j:\!\[\e[1;30m\]]\[\e[0;36m\] \T \d \[\e[1;30m\][\[\e[1;34m\]\u@\H\[\e[1;30m\]:\[\e[0;37m\]${SSH_TTY} \[\e[0;32m\]+${SHLVL}\[\e[1;30m\]] \[\e[1;37m\]\w\[\e[0;37m\] \n($SHLVL:\!)\$ '

### List of colors for prompt and Bash

Add this to your Bash file(s) to define colors for prompt and commands:

    txtblk='\e[0;30m' # Black - Regular
    txtred='\e[0;31m' # Red
    txtgrn='\e[0;32m' # Green
    txtylw='\e[0;33m' # Yellow
    txtblu='\e[0;34m' # Blue
    txtpur='\e[0;35m' # Purple
    txtcyn='\e[0;36m' # Cyan
    txtwht='\e[0;37m' # White
    bldblk='\e[1;30m' # Black - Bold
    bldred='\e[1;31m' # Red
    bldgrn='\e[1;32m' # Green
    bldylw='\e[1;33m' # Yellow
    bldblu='\e[1;34m' # Blue
    bldpur='\e[1;35m' # Purple
    bldcyn='\e[1;36m' # Cyan
    bldwht='\e[1;37m' # White
    unkblk='\e[4;30m' # Black - Underline
    undred='\e[4;31m' # Red
    undgrn='\e[4;32m' # Green
    undylw='\e[4;33m' # Yellow
    undblu='\e[4;34m' # Blue
    undpur='\e[4;35m' # Purple
    undcyn='\e[4;36m' # Cyan
    undwht='\e[4;37m' # White
    bakblk='\e[40m'   # Black - Background
    bakred='\e[41m'   # Red
    bakgrn='\e[42m'   # Green
    bakylw='\e[43m'   # Yellow
    bakblu='\e[44m'   # Blue
    bakpur='\e[45m'   # Purple
    bakcyn='\e[46m'   # Cyan
    bakwht='\e[47m'   # White
    txtrst='\e[0m'    # Text Reset

Or if you prefer color names you will know how to spell without a special decoder ring and want high intensity colors:

    # Reset
    Color_Off='\e[0m'       # Text Reset

    # Regular Colors
    Black='\e[0;30m'        # Black
    Red='\e[0;31m'          # Red
    Green='\e[0;32m'        # Green
    Yellow='\e[0;33m'       # Yellow
    Blue='\e[0;34m'         # Blue
    Purple='\e[0;35m'       # Purple
    Cyan='\e[0;36m'         # Cyan
    White='\e[0;37m'        # White

    # Bold
    BBlack='\e[1;30m'       # Black
    BRed='\e[1;31m'         # Red
    BGreen='\e[1;32m'       # Green
    BYellow='\e[1;33m'      # Yellow
    BBlue='\e[1;34m'        # Blue
    BPurple='\e[1;35m'      # Purple
    BCyan='\e[1;36m'        # Cyan
    BWhite='\e[1;37m'       # White

    # Underline
    UBlack='\e[4;30m'       # Black
    URed='\e[4;31m'         # Red
    UGreen='\e[4;32m'       # Green
    UYellow='\e[4;33m'      # Yellow
    UBlue='\e[4;34m'        # Blue
    UPurple='\e[4;35m'      # Purple
    UCyan='\e[4;36m'        # Cyan
    UWhite='\e[4;37m'       # White

    # Background
    On_Black='\e[40m'       # Black
    On_Red='\e[41m'         # Red
    On_Green='\e[42m'       # Green
    On_Yellow='\e[43m'      # Yellow
    On_Blue='\e[44m'        # Blue
    On_Purple='\e[45m'      # Purple
    On_Cyan='\e[46m'        # Cyan
    On_White='\e[47m'       # White

    # High Intensity
    IBlack='\e[0;90m'       # Black
    IRed='\e[0;91m'         # Red
    IGreen='\e[0;92m'       # Green
    IYellow='\e[0;93m'      # Yellow
    IBlue='\e[0;94m'        # Blue
    IPurple='\e[0;95m'      # Purple
    ICyan='\e[0;96m'        # Cyan
    IWhite='\e[0;97m'       # White

    # Bold High Intensity
    BIBlack='\e[1;90m'      # Black
    BIRed='\e[1;91m'        # Red
    BIGreen='\e[1;92m'      # Green
    BIYellow='\e[1;93m'     # Yellow
    BIBlue='\e[1;94m'       # Blue
    BIPurple='\e[1;95m'     # Purple
    BICyan='\e[1;96m'       # Cyan
    BIWhite='\e[1;97m'      # White

    # High Intensity backgrounds
    On_IBlack='\e[0;100m'   # Black
    On_IRed='\e[0;101m'     # Red
    On_IGreen='\e[0;102m'   # Green
    On_IYellow='\e[0;103m'  # Yellow
    On_IBlue='\e[0;104m'    # Blue
    On_IPurple='\e[0;105m'  # Purple
    On_ICyan='\e[0;106m'    # Cyan
    On_IWhite='\e[0;107m'   # White

To use in commands from your shell environment:

$ echo -e "${txtblu}test"
test
$ echo -e "${bldblu}test"
test
$ echo -e "${undblu}test"
test
$ echo -e "${bakblu}test"
test
$ _

To use in a prompt (note double quotes to enable $color variable expansion and \[ \] escapes around them so they are not counted as character positions and the cursor position is not wrong):

    PS1="\[$txtblu\]foo\[$txtred\] bar\[$txtrst\] baz : "

If you experience premature line wrapping when entering commands at the prompt then missing escapes is most likely to be the reason.

### Prompt escapes

The various Bash prompt escapes listed in the manpage:

    Bash allows these prompt strings to be customized by inserting a
    number of ''backslash-escaped special characters'' that are
    decoded as follows:

    	\a		an ASCII bell character (07)
    	\d		the date in "Weekday Month Date" format (e.g., "Tue May 26")
    	\D{format}	the format is passed to strftime(3) and the result
    			  is inserted into the prompt string an empty format
    			  results in a locale-specific time representation.
    			  The braces are required
    	\e		an ASCII escape character (033)
    	\h		the hostname up to the first `.'
    	\H		the hostname
    	\j		the number of jobs currently managed by the shell
    	\l		the basename of the shell's terminal device name
    	\n		newline
    	\r		carriage return
    	\s		the name of the shell, the basename of $0 (the portion following
    			  the final slash)
    	\t		the current time in 24-hour HH:MM:SS format
    	\T		the current time in 12-hour HH:MM:SS format
    	\@		the current time in 12-hour am/pm format
    	\A		the current time in 24-hour HH:MM format
    	\u		the username of the current user
    	\v		the version of bash (e.g., 2.00)
    	\V		the release of bash, version + patch level (e.g., 2.00.0)
    	\w		the current working directory, with $HOME abbreviated with a tilde
    	\W		the basename of the current working directory, with $HOME
    			 abbreviated with a tilde
    	\!		the history number of this command
    	\#		the command number of this command
    	\$		if the effective UID is 0, a #, otherwise a $
    	\nnn		the character corresponding to the octal number nnn
    	\\		a backslash
    	\[		begin a sequence of non-printing characters, which could be used
    			  to embed a terminal control sequence into the prompt
    	\]		end a sequence of non-printing characters

    	The command number and the history number are usually different:
    	the history number of a command is its position in the history
    	list, which may include commands restored from the history file
    	(see HISTORY below), while the command number is the position in
    	the sequence of commands executed during the current shell session.
    	After the string is decoded, it is expanded via parameter
    	expansion, command substitution, arithmetic expansion, and quote
    	removal, subject to the value of the promptvars shell option (see
    	the description of the shopt command under SHELL BUILTIN COMMANDS
    	below).

### Positioning the cursor

The following sequence sets the cursor position:

    \[\033[<row>;<column>f\]

The current cursor position can be saved using:

    \[\033[s\]

To restore a position, use the following sequence:

    \[\033[u\]

The following example uses these sequences to display the time in the upper right corner:

    PS1=">\[\033[s\]\[\033[1;\$((COLUMNS-4))f\]\$(date +%H:%M)\[\033[u\]"

The environment variable COLUMNS contains the number of columns of the terminal. The above example substracts 4 from its value in order to justify the five character wide output of date at the right border.

### Return value visualisation

Use this prompt if you want to see the return value of the last executed command.

    #return value visualisation
    PS1="\$? \$(if [[ \$? == 0 ]]; then echo \"\[\033[0;32m\];)\"; else echo \"\[\033[0;31m\];(\"; fi)\[\033[00m\] : "

This will give you basic prompt:

0 ;) : true
0 ;) : false
1 ;( :

Zero is a green smiley (replace it with anything you want) and non-zero is a red one. So your prompt will smile if the last operation was successful.

But you will probably want to use the return value in your own prompt, like this:

0 ;) andy@alba ~ $ true
0 ;) andy@alba ~ $ false
1 ;( andy@alba ~ $ _

with a code like this one:

    #return value visualisation
    PS1="\[\033[01;37m\]\$? \$(if [[ \$? == 0 ]]; then echo \"\[\033[01;32m\];)\"; else echo \"\[\033[01;31m\];(\"; fi) $(if [[ ${EUID} == 0 ]]; then echo '\[\033[01;31m\]\h'; else echo '\[\033[01;32m\]\u@\h'; fi)\[\033[01;34m\] \w \$\[\033[00m\] "

Or, if you want, you can build your prompt using the ✓ unicode symbol for a zero status and the ✗ unicode symbol for a nonzero status:

0 ✓ andy@alba ~ $ true
0 ✓ andy@alba ~ $ false
1 ✗ andy@alba ~ $ I\ will\ try\ to\ type\ a\ wrong\ command...
bash: I will try to type a wrong command...: command not found
127 ✗ andy@alba ~ $ _

starting from a code like this other one:

    #return value visualisation
    PS1="\[\033[01;37m\]\$? \$(if [[ \$? == 0 ]]; then echo \"\[\033[01;32m\]\342\234\223\"; else echo \"\[\033[01;31m\]\342\234\227\"; fi) $(if [[ ${EUID} == 0 ]]; then echo '\[\033[01;31m\]\h'; else echo '\[\033[01;32m\]\u@\h'; fi)\[\033[01;34m\] \w \$\[\033[00m\] "

Here's an alternative that only include the error status if it is nonzero:

    PROMPT_COMMAND='es=$?; [[ $es -eq 0 ]] && unset error || error=$(echo -e "\e[1;41m $es \e[40m")'
    PS1="${error} ${PS1}"

### Wolfman's

After reading through most of the Bash Prompt Howto, the author developed a color bash prompt that displays the last 25 characters of the current working directory. This prompt should work well on terminals with a black background. The following code goes in file `~/.bashrc`.

- Add the bash_prompt_command function. If you have a couple directories with long names or start entering a lot of subdirectories, this function will keep the command prompt from wrapping around the screen by displaying at most the last pwdmaxlen characters from the PWD. This code was taken from the Bash Prompt Howto's section on Controlling the Size and Appearance of $PWD and modified to replace the user's home directory with a tilde.

    ##################################################
    # Fancy PWD display function
    ##################################################
    # The home directory (HOME) is replaced with a ~
    # The last pwdmaxlen characters of the PWD are displayed
    # Leading partial directory names are striped off
    # /home/me/stuff		-> ~/stuff			if USER=me
    # /usr/share/big_dir_name	-> ../share/big_dir_name	if pwdmaxlen=20
    ##################################################

    bash_prompt_command() {
    	# How many characters of the $PWD should be kept
    	local pwdmaxlen=25
    	# Indicate that there has been dir truncation
    	local trunc_symbol=".."
    	local dir=${PWD##*/}
    	pwdmaxlen=$(( ( pwdmaxlen < ${#dir} ) ? ${#dir} : pwdmaxlen ))
    	NEW_PWD=${PWD/#$HOME/\~}
    	local pwdoffset=$(( ${#NEW_PWD} - pwdmaxlen ))
    	if [ ${pwdoffset} -gt "0" ]
    	then
    		NEW_PWD=${NEW_PWD:$pwdoffset:$pwdmaxlen}
    		NEW_PWD=${trunc_symbol}/${NEW_PWD#*/}
    	fi
    }

- The next fragment generates the command prompt and various colors are defined. The user's color for the username, hostname, and prompt ($ or #) is set to cyan, and if the user is root (root's UID is always 0), set the color to red. The command prompt is set to a colored version of Arch's default with the NEW_PWD from the last function.

  Also, make sure that your color variables are enclosed in double and not single quote marks. Using single quote marks seems to give Bash problems with line wrapping correctly.

    bash_prompt() {
    	case $TERM in
    		xterm*|rxvt*)
    			local TITLEBAR='\[\033]0;\u:${NEW_PWD}\007\]'
    			;;
    		*)
    			local TITLEBAR=""
    			;;
    	esac
    	local NONE="\[\033[0m\]"	# unsets color to term's fg color

    	# regular colors
    	local K="\[\033[0;30m\]"	# black
    	local R="\[\033[0;31m\]"	# red
    	local G="\[\033[0;32m\]"	# green
    	local Y="\[\033[0;33m\]"	# yellow
    	local B="\[\033[0;34m\]"	# blue
    	local M="\[\033[0;35m\]"	# magenta
    	local C="\[\033[0;36m\]"	# cyan
    	local W="\[\033[0;37m\]"	# white

    	# emphasized (bolded) colors
    	local EMK="\[\033[1;30m\]"
    	local EMR="\[\033[1;31m\]"
    	local EMG="\[\033[1;32m\]"
    	local EMY="\[\033[1;33m\]"
    	local EMB="\[\033[1;34m\]"
    	local EMM="\[\033[1;35m\]"
    	local EMC="\[\033[1;36m\]"
    	local EMW="\[\033[1;37m\]"

    	# background colors
    	local BGK="\[\033[40m\]"
    	local BGR="\[\033[41m\]"
    	local BGG="\[\033[42m\]"
    	local BGY="\[\033[43m\]"
    	local BGB="\[\033[44m\]"
    	local BGM="\[\033[45m\]"
    	local BGC="\[\033[46m\]"
    	local BGW="\[\033[47m\]"

    	local UC=$W			# user's color
    	[ $UID -eq "0" ] && UC=$R	# root's color

    	PS1="$TITLEBAR ${EMK}[${UC}\u${EMK}@${UC}\h ${EMB}\${NEW_PWD}${EMK}]${UC}\\$ ${NONE}"
    	# without colors: PS1="[\u@\h \${NEW_PWD}]\\$ "
    	# extra backslash in front of \$ to make bash colorize the prompt
    }

- Finally, append this code. This ensures that the NEW_PWD variable will be updated when you cd somewhere else, and it sets the PS1 variable, which contains the command prompt.

    PROMPT_COMMAND=bash_prompt_command
    bash_prompt
    unset bash_prompt

### KitchM's

These prompts offer a little more flash and visual clarity. Note that the use of red in the root user's prompt should provide ample warning. That is not to say someone could not use flashing text or arrow to do even more, but these will give you a good starting point.

First, change the default background in your terminal preferences (this example uses Xfce's Terminal program) to #D2D2D2, and the text color to #000000. The font is listed as DejaVu Sans Mono Book 12. The cursor color is #00AA00, and the tab activity color is #AF0000.

Second, in ~/.bashrc and right after the PS1= line, enter a new line with the following:

    PS1='\e[1;33;47m\u \e[1;32;47mon \h \e[1;35;47m\d \@\e[0;0m\n\e[1;34m[dir.= \w] \# > \e[0;0m'

And then place a # in front of the first PS1 line to remark it out.

Third, for root user, edit /root/.bashrc in the same manner to include:

    PS1='\e[1;31;47m\u \e[1;32;47mon \h \e[1;35;47m\d \@\e[0;0m\n\e[1;31m[dir.= \w] \# > \e[0;0m'

Do not forget to comment out the old line.

These are double-line prompts, and they should look something like these:

  user

Root on myhost Sun Jan 15 12:30 PM
[dir.= /etc/rc.d] 1 >

  root

Root on myhost Sun Jan 15 12:30 PM
[dir.= /etc/rc.d] 1 >

You will note that the background colors make them easier to read, and the text colors just keep things interesting. There is a lot of leeway to make them personalized, just with the use of colors. Enjoy!

## Set window title

Xterm and many other terminal emulators (including PuTTY) allow you to set the window title using special escape sequences. You can define the `${XTERM_TITLE}` variable as follows, then insert it at the beginning of the prompt to set xterm title (if available) to directory@user@hostname:

    #set xterm title
    case "$TERM" in
    	xterm | xterm-color)
    		XTERM_TITLE='\[\e]0;\W@\u@\H\a\]'
    	;;
    esac

The text between `0;` and `\a` can be set to anything you like, for example:

    export PS1="\[\e]0;Welcome to ArchLinux\a\]\$>> "

sets the window title to "Welcome to ArchLinux" and displays this simple prompt:

$>> _

## Different colors for text entry and console output

If you do not reset the text color at the end of your prompt, both the text you enter and the console text will simply stay in that color. If you want to edit text in a special color but still use the default color for command output, you will need to reset the color after you press enter, but still before any commands get run. You can do this by installing a DEBUG trap in your ~/.bashrc, like this:

    trap 'echo -ne "\e[0m"' DEBUG

## Laptop battery status on prompt

Read this article and this post for details.

## See also

- gentoo-bashrc from AUR
- tput(1)
- Colours and Cursor Movement With tput

## External links

- Forum Discussions:
  - BASH prompt
  - What's your PS1?
- http://www.tldp.org/HOWTO/Bash-Prompt-HOWTO/x329.html
- Giles Orr's collection of sample prompts

Categories:

- Eye candy (简体中文)
- Command shells (简体中文)