Bash script count down 5 minutes display on single line [closed]

Question

I would like to have a count down of 5 minutes, updating every second and showing the result on the same line. Is this even possible with Bash scripting?

Answer 1

This works from Bash shell:

secs=$((5 * 60))
while [ $secs -gt 0 ]; do
   echo -ne "$secs\033[0K\r"
   sleep 1
   : $((secs--))
done

The special character \033[0K represents an end of line which cleans the rest of line if there are any characters left from previous output and \r is a carriage return which moves the cursor to the beginning of the line. There is a nice thread about this feature at stackoverflow.com.

You can add own commands or whatever in the while loop. If you need something more specific please provide me more details.

Answer 2

Here's one with an improvement of right output format (HH:MM:SS) with proper leading zeros and supporting hours:

#!/bin/bash

m=${1}-1 # add minus 1 

Floor () {
  DIVIDEND=${1}
  DIVISOR=${2}
  RESULT=$(( ( ${DIVIDEND} - ( ${DIVIDEND} % ${DIVISOR}) )/${DIVISOR} ))
  echo ${RESULT}
}

Timecount(){
        s=${1}
        HOUR=$( Floor ${s} 60/60 )
        s=$((${s}-(60*60*${HOUR})))
        MIN=$( Floor ${s} 60 )
        SEC=$((${s}-60*${MIN}))
     while [ $HOUR -ge 0 ]; do
        while [ $MIN -ge 0 ]; do
                while [ $SEC -ge 0 ]; do
                        printf "%02d:%02d:%02d\033[0K\r" $HOUR $MIN $SEC
                        SEC=$((SEC-1))
                        sleep 1
                done
                SEC=59
                MIN=$((MIN-1))
        done
        MIN=59
        HOUR=$((HOUR-1))
     done
}

Timecount $m

Gives an output that looks like this:

02:04:15