Question

I found a good customization to my .bashrc for my prompt to show extra information and provide color highlighting. Here’s what I have:

# ----- Define a few Colors
BLACK='\e[0;30m'
BLUE='\e[0;34m'
GREEN='\e[0;32m'
CYAN='\e[0;36m'
RED='\e[0;31m'
PURPLE='\e[0;35m'
BROWN='\e[0;33m'
LIGHTGRAY='\e[0;37m'
DARKGRAY='\e[1;30m'
LIGHTBLUE='\e[1;34m'
LIGHTGREEN='\e[1;32m'
LIGHTCYAN='\e[1;36m'
LIGHTRED='\e[1;31m'
LIGHTPURPLE='\e[1;35m'
YELLOW='\e[1;33m'
WHITE='\e[1;37m'

function __setprompt {
  local SSH_IP=`echo $SSH_CLIENT | awk '{ print $1 }'`
  local SSH2_IP=`echo $SSH2_CLIENT | awk '{ print $1 }'`
  if [ $SSH2_IP ] || [ $SSH_IP ] ; then
    local SSH_FLAG="@\h"
  fi
  PS1="$CYAN[\u$SSH_FLAG:$BROWN\w$CYAN]\\$ $NOCOLOR"
  PS2="$CYAN>$NOCOLOR "
  PS4='$CYAN+$NOCOLOR '
}
__setprompt

The issue I’m running into is that it doesn’t handle wrapping text correctly (see below screenshot). Can anyone offer any advice on what the problem might be? It looks like it doesn’t adjust at all what is typed in by the user.

Answer 1

what’s the value of CYAN BROWN NOCOLOR vars ?
You most problably forgot to wrap them in \[ and \],
to mark them as non-printing characters.

if your CYAN is

CYAN="\e[0;36m"

you need to wrap it in \[ and \], like

CYAN="\[\e[0;36m\]"

---

otherwise, wrap the vars themselves in the prompt variables, like

PS2="\[$CYAN\]>\[$NOCOLOR\] "

see the comments here:

function __setprompt {
  local SSH_IP="${SSH_CLIENT%% *}"      # no need for echo/awk/sed
  local SSH2_IP="${SSH2_CLIENT%% *}"    # use parameter expansion instead
  if [[ -n "$SSH2_IP" || -n "$SSH_IP" ]]; then  # bash uses double brakets
    local SSH_FLAG="@\h"                        # and the OR operator works inside
  fi
  PS1="\[$CYAN\][\u$SSH_FLAG:\[$BROWN\]\w\[$CYAN\]]\\$ \[$NOCOLOR\]"  # dont mess with [ and ]
  PS2="\[$CYAN\]>\[$NOCOLOR\] "                                       # only wrap color vars in \[ and \]
  PS4="\[$CYAN\]+\[$NOCOLOR\] "                 # single quotes will not expand $vars
}
__setprompt

---

also, have a look at PROMPT_COMMAND variable,

PROMPT_COMMAND
If set, the value is executed as a command prior to issuing each primary prompt.

and also note that by convension capital variable names are kept to be used by the environment