Custom Bash Prompt Line Wrap Issue

[quasarcannon]

I have a fairly complex bash prompt with some builtins. It shows battery percent, memory percent, and HDD space left all in colors. The colors even change when not plugged in, or low memory left.

The problem is that the line wraps about 3/4 from the end to the beginning of the same line, so commands overwrite themselves and I cannot see them.

I originally posted in ubuntuforums but there are no bites yet.
It seems that I cannot post any URLs here until I have 15 posts...[sigh]. But it has helpful images.
It is at ubuntu forums. The thread is 1285442 and the title is "Custom Bash Prompt Line Wrap Issue".

Here is the script:

shopt -s checkwinsize

#Defining Colors Used
RED='\e[0;31m'
REDWARNING='\e[4;31m'
GREEN='\e[0;32m'
YELLOW='\e[1;33m'
ORANGE='\e[0;33m'
BLUE='\e[0;34m'
MAGENTA='\e[0;35m'
WHITE='\e[0m'
GREY='\e[1;30m'

myprompt()
{
#VARS
REM=`awk '/remaining capacity/ { print $3 }' /proc/acpi/battery/BAT0/state`
LAST=`awk '/last full/ { print $4}' /proc/acpi/battery/BAT0/info`
CHARGESTATE=`awk '/charging state/ { print $3 }' /proc/acpi/battery/BAT0/state`
SPACE=`df -h | awk 'NR==2{ print $4 }'`
MEMTOT=`free -m | awk 'NR==2{print $2}'`
MEMUSED=`free -m | awk 'NR==3{print $3}'`

CHARGEPERCENT=`echo $REM $LAST | awk '{printf "%d", ($1/$2)*100'}`


case "${CHARGESTATE}" in
   'charged')
   CHARGECOLOR="$GREEN+"
   ;;
   'charging')
   CHARGECOLOR="$YELLOW+"
   ;;
   'discharging')
   if [ "$CHARGEPERCENT" -le "30" ] ; then
     CHARGECOLOR="$REDWARNING-"
   else
     CHARGECOLOR="$YELLOW-"
   fi
   ;;
esac

MEMPERCENT=`echo $MEMTOT $MEMUSED | awk '{printf "%d", ($2/$1)*100'}`

if [ $MEMPERCENT -ge "90" ] ; then
   MEMCOLOR=$RED
else
   MEMCOLOR=$MAGENTA
fi

echo -e "$GREY|${CHARGECOLOR}${CHARGEPERCENT}%$GREY|$ORANGE${SPACE}$GREY|${MEMCOLOR}${MEMPERCENT}%$GREY|"

}

PS1="${debian_chroot:+($debian_chroot)}\$(myprompt)$BLUE\w$WHITE\$ "

Anybody understand enough bash to help me? Or maybe point me somewhere where I can get help?

[drl]

Hi.

I had the same wrapping behavior, and modifying a previous command (history) did not always work well.

When I applied the advice to the prompt setting as noted here Readline problems - The UNIX and Linux Forums the problem went away for me:

... use the \[ escape to begin a sequence of non-printing characters,
and the \] escape to signal the end of such a sequence

I also used \033 in place of \e.

Specifically, here is my bash prompt:

export PS1="\[\033[0;31m\]\u \h \W $ \[\033[0m\] "

Let us know if this works for you ... cheers, drl

A few other links:

Tip: Prompt magic

How to make custom prompts (scroll down to the bash section)

[quasarcannon]

Someone on Ubuntuforums helped within an hour of my last message. Must have hit it at the right time.

As for your fix; I could't add escape brackets to my PS1 line because of the scripts. The fix that worked is this:

There seems to be some unresolved issues with a "live" prompt command that issues
terminal control signals. You could use the PROMPT_COMMAND to work around this.

Also, non-printing characters within a prompt should be enclosed in \[ and \].

Replace your PS1 line with these 2:
Code:



	
	
PROMPT_COMMAND='myprompt'
PS1="\[$BLUE\]\w\[$WHITE\]\$ "
 
 ^you also have to change the `echo -e` line to `echo -ne` to complete the illusion.

The only glitches I've seen out of this method so far are
control+L clearing and control+R searching.

Thank you for the quick reply.

[quasarcannon]

Here is the working code for anyone who wants it.

###___________MY COOL STUFFS__________###
shopt -s checkwinsize                    

#Defining Colors Used
RED='\e[0;31m'       
REDWARNING='\e[4;31m'
GREEN='\e[0;32m'     
YELLOW='\e[1;33m'    
ORANGE='\e[0;33m'    
BLUE='\e[0;34m'      
MAGENTA='\e[0;35m'   
WHITE='\e[0m'        
GREY='\e[1;30m'      

myprompt()
{         
#VARS     
REM=`awk '/remaining capacity/ { print $3 }' /proc/acpi/battery/BAT0/state`
LAST=`awk '/last full/ { print $4 }' /proc/acpi/battery/BAT0/info`         
CHARGESTATE=`awk '/charging state/ { print $3 }' /proc/acpi/battery/BAT0/state`
SPACE=`df -h . | awk 'NR==2{ print $4 }'`                                      
MEMTOT=`free -m | awk 'NR==2{ print $2 }'`                                     
MEMUSED=`free -m | awk 'NR==3{ print $3 }'`                                    

CHARGEPERCENT=`echo $REM $LAST | awk '{printf "%d", ($1/$2)*100'}`


case "${CHARGESTATE}" in
   'charged')           
   CHARGECOLOR="$GREEN+"
   ;;                   
   'charging')          
   CHARGECOLOR="$YELLOW+"
   ;;
   'discharging')
   if [ "$CHARGEPERCENT" -le "30" ] ; then
     CHARGECOLOR="$REDWARNING-"
   else
     CHARGECOLOR="$YELLOW-"
   fi
   ;;
esac

MEMPERCENT=`echo $MEMTOT $MEMUSED | awk '{printf "%d", ($2/$1)*100'}`

if [ $MEMPERCENT -ge "90" ] ; then
   MEMCOLOR=$RED
else
   MEMCOLOR=$MAGENTA
fi

#echo -e "$GREY|${CHARGECOLOR}${CHARGEPERCENT}%$GREY|$ORANGE${SPACE}$GREY|${MEMCOLOR}${MEMPERCENT}%$GREY|"
echo -ne "$GREY|${CHARGECOLOR}${CHARGEPERCENT}%$GREY|$ORANGE${SPACE}$GREY|${MEMCOLOR}${MEMPERCENT}%$GREY|"
}

#PS1="${debian_chroot:+($debian_chroot)}\$(myprompt)$BLUE\w$WHITE\$ "
PROMPT_COMMAND='myprompt'
PS1="\[$BLUE\]\w\[$WHITE\]\$ "