Using Bash to display a progress indicator (spinner)

Question

Using a bash only script, how can you provide a bash progress indicator?

For example, when I run a command from bash - while that command is executing - let the user know that something is still happening.

Answer 1

In this example using SCP, I'm demonstrating how to grab the process id (pid) and then do something while that process is running.

This displays a simple spinnng icon.

/usr/bin/scp me@website.com:file somewhere 2>/dev/null &
pid=$! # Process Id of the previous running command

spin[0]="-"
spin[1]="\\"
spin[2]="|"
spin[3]="/"

echo -n "[copying] ${spin[0]}"
while [ kill -0 $pid ]
do
  for i in "${spin[@]}"
  do
        echo -ne "\b$i"
        sleep 0.1
  done
done

---

William Pursell's solution

/usr/bin/scp me@website.com:file somewhere 2>/dev/null &
pid=$! # Process Id of the previous running command

spin='-\|/'

i=0
while kill -0 $pid 2>/dev/null
do
  i=$(( (i+1) %4 ))
  printf "\r${spin:$i:1}"
  sleep .1
done

Answer 2

If you have a way to estimate percentage done, such as the current number of files processed and total number, you can make a simple linear progress meter with a little math and assumptions about screen width.

count=0
total=34
pstr="[=======================================================================]"

while [ $count -lt $total ]; do
  sleep 0.5 # this is work
  count=$(( $count + 1 ))
  pd=$(( $count * 73 / $total ))
  printf "\r%3d.%1d%% %.${pd}s" $(( $count * 100 / $total )) $(( ($count * 1000 / $total) % 10 )) $pstr
done

Or instead of a linear meter you could estimate time remaining. It's about as accurate as other similar things.

count=0
total=34
start=`date +%s`

while [ $count -lt $total ]; do
  sleep 0.5 # this is work
  cur=`date +%s`
  count=$(( $count + 1 ))
  pd=$(( $count * 73 / $total ))
  runtime=$(( $cur-$start ))
  estremain=$(( ($runtime * $total / $count)-$runtime ))
  printf "\r%d.%d%% complete ($count of $total) - est %d:%0.2d remaining\e[K" $(( $count*100/$total )) $(( ($count*1000/$total)%10)) $(( $estremain/60 )) $(( $estremain%60 ))
done
printf "\ndone\n"

Answer 3

Referred from here is a nice spinner function (with slight modification), will help your cursor to stay in original position also.

spinner()
{
    local pid=$!
    local delay=0.75
    local spinstr='|/-\'
    while [ "$(ps a | awk '{print $1}' | grep $pid)" ]; do
        local temp=${spinstr#?}
        printf " [%c]  " "$spinstr"
        local spinstr=$temp${spinstr%"$temp"}
        sleep $delay
        printf "\b\b\b\b\b\b"
    done
    printf "    \b\b\b\b"
}

with usage:

(a_long_running_task) &
spinner

Answer 4

This is a pretty easy technique:
(just replace sleep 20 with whatever command you want to indicate is running)

#!/bin/bash

sleep 20 & PID=$! #simulate a long process

echo "THIS MAY TAKE A WHILE, PLEASE BE PATIENT WHILE ______ IS RUNNING..."
printf "["
# While process is running...
while kill -0 $PID 2> /dev/null; do 
    printf  "▓"
    sleep 1
done
printf "] done!"

The output looks like this:

> THIS MAY TAKE A WHILE, PLEASE BE PATIENT WHILE ______ IS RUNNING...
> [▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓] done!

It adds a ▓ (high density dotted) every second until the process is complete.

Answer 5

Here a simple one-liner, that I use:

while true; do for X in '-' '/' '|' '\'; do echo -en "\b$X"; sleep 0.1; done; done 

Answer 6

Here's my attempt. I'm new to bash scripts so some of this code may be terrible :)

Example Output:

The Code:

progressBarWidth=20

# Function to draw progress bar
progressBar () {

  # Calculate number of fill/empty slots in the bar
  progress=$(echo "$progressBarWidth/$taskCount*$tasksDone" | bc -l)  
  fill=$(printf "%.0f\n" $progress)
  if [ $fill -gt $progressBarWidth ]; then
    fill=$progressBarWidth
  fi
  empty=$(($fill-$progressBarWidth))

  # Percentage Calculation
  percent=$(echo "100/$taskCount*$tasksDone" | bc -l)
  percent=$(printf "%0.2f\n" $percent)
  if [ $(echo "$percent>100" | bc) -gt 0 ]; then
    percent="100.00"
  fi

  # Output to screen
  printf "\r["
  printf "%${fill}s" '' | tr ' ' ▉
  printf "%${empty}s" '' | tr ' ' ░
  printf "] $percent%% - $text "
}



## Collect task count
taskCount=33
tasksDone=0

while [ $tasksDone -le $taskCount ]; do

  # Do your task
  (( tasksDone += 1 ))

  # Add some friendly output
  text=$(echo "somefile-$tasksDone.dat")

  # Draw the progress bar
  progressBar $taskCount $taskDone $text

  sleep 0.01
done

echo

You can see the source here: https://gist.github.com/F1LT3R/fa7f102b08a514f2c535

Answer 7

Here is an example of an 'activity indicator,' for an internet connection speed test via the linux 'speedtest-cli' command:

## BASH shell
printf '\n\tInternet speed test:  '

# http://stackoverflow.com/questions/12498304/using-bash-to-display-a-progress-working-indicator

spin[0]="-"
spin[1]="\\"
spin[2]="|"
spin[3]="/"

# http://stackoverflow.com/questions/20165057/executing-bash-loop-while-command-is-running

speedtest > .st.txt &           ## & : continue running script
pid=$!                          ## PID of last command

# If this script is killed, kill 'speedtest':
trap "kill $pid 2> /dev/null" EXIT

# While 'speedtest' is running:
while kill -0 $pid 2> /dev/null; do
for i in "${spin[@]}"
do
    echo -ne "\b$i"
    sleep 0.1
done
done

# Disable the trap on a normal exit:
trap - EXIT

printf "\n\t           "
grep Download: .st.txt
printf "\t             "
grep Upload: .st.txt
echo ''
rm -f st.txt

Update - example:

Answer 8

Aside from the classical spinner, you can use this progress bar

It achieves subcharacter precision by using half block characters

Code included on the link.

Answer 9

https://github.com/extensionsapp/progre.sh

Create 82 percent progress: progreSh 82

Answer 10

I extended the answer of checksum in his answer by displaying a variable info message after the spinner:

#!/usr/bin/env bash 
function spinner() {
    local info="$1"
    local pid=$!
    local delay=0.75
    local spinstr='|/-\'
    while kill -0 $pid 2> /dev/null; do
        local temp=${spinstr#?}
        printf " [%c]  $info" "$spinstr"
        local spinstr=$temp${spinstr%"$temp"}
        sleep $delay
        local reset="\b\b\b\b\b\b"
        for ((i=1; i<=$(echo $info | wc -c); i++)); do
            reset+="\b"
        done
        printf $reset
    done
    printf "    \b\b\b\b"
}

# usage:
(a_long_running_task) &
spinner "performing long running task..."

I don't like that if the stdout output with a spinner is redirected to a file, less shows ^H for each backspace instead of avoiding them in a file output at all. Is that possible with an easy spinner like this one?

Answer 11

@DavidD's comments on Pez Cuckows answer, this is an example of how you can capture the output of the progress bar in a script and still see the spinner on the screen:

#!/usr/bin/env bash 

#############################################################################
###########################################################################
###
### Modified/Rewritten by A.M.Danischewski (c) 2015 v1.1
### Issues: If you find any issues emai1 me at my <first name> dot 
###         <my last name> at gmail dot com.  
###
### Based on scripts posted by Pez Cuckow, William Pursell at:  
### http://stackoverflow.com/questions/12498304/using-bash-to-display-\
###      a-progress-working-indicator
###
### This program runs a program passed in and outputs a timing of the 
### command and it exec's a new fd for stdout so you can assign a 
### variable the output of what was being run. 
### 
### This is a very new rough draft but could be expanded. 
### 
### This program is free software: you can redistribute it and/or modify
### it under the terms of the GNU General Public License as published by
### the Free Software Foundation, either version 3 of the License, or
### (at your option) any later version.
###
### This program is distributed in the hope that it will be useful,
### but WITHOUT ANY WARRANTY; without even the implied warranty of
### MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
### GNU General Public License for more details.
###
### You should have received a copy of the GNU General Public License
### along with this program.  If not, see <http://www.gnu.org/licenses/>.
###########################################################################
#############################################################################

declare    CMD="${1}"
shift      ## Clip the first value of the $@, the rest are the options. 
declare    CMD_OPTIONS="$@"
declare    CMD_OUTPUT=""
declare    TMP_OUTPUT="/tmp/_${0##*/}_$$_$(date +%Y%m%d%H%M%S%N)" 
declare -r SPIN_DELAY="0.1"
declare -i PID=

function usage() {
cat <<EOF

Description: ${0##*/}

This program runs a program passed in and outputs a timing of the 
command and it exec's a new fd for stdout so you can assign a variable 
the output of what was being run. 

Usage: ${0##*/} <command> [command options]

 E.g.  
    >$ ${0##*/} sleep 5 \&\& echo "hello" \| figlet
     Running: sleep 5 && echo hello | figlet, PID 2587:/

     real   0m5.003s
     user   0m0.000s
     sys    0m0.002s
      _          _ _       
     | |__   ___| | | ___  
     | '_ \ / _ \ | |/ _ \ 
     | | | |  __/ | | (_) |
     |_| |_|\___|_|_|\___/ 

     Done..
    >$ var=\$(${0##*/} sleep 5 \&\& echo hi)
     Running: sleep 5 && echo hi, PID 32229:-
     real   0m5.003s
     user   0m0.000s
     sys    0m0.001s
     Done..
     >$ echo \$var
     hi

EOF
} 

function spin_wait() { 
 local -a spin 
 spin[0]="-"
 spin[1]="\\"
 spin[2]="|"
 spin[3]="/"
 echo -en "Running: ${CMD} ${CMD_OPTIONS}, PID ${PID}: " >&3
 while kill -0 ${PID} 2>/dev/random; do
   for i in "${spin[@]}"; do
     echo -ne "\b$i" >&3
     sleep ${SPIN_DELAY}
   done
 done
} 

function run_cmd() { 
 exec 3>$(tty)
 eval "time ${CMD} ${CMD_OPTIONS}" 2>>"${TMP_OUTPUT}" | tee "${TMP_OUTPUT}" & 
 PID=$! # Set global PID to process id of the command we just ran. 
 spin_wait
 echo -en "\n$(< "${TMP_OUTPUT}")\n" >&3 
 echo -en "Done..\n" >&3
 rm "${TMP_OUTPUT}"
 exec 3>&-
} 

if [[ -z "${CMD}" || "${CMD}" =~ ^-. ]]; then 
 usage | more && exit 0 
else 
 run_cmd  
fi 

exit 0 

Answer 12

Psychedelic progress bar for bash scripting. Call by command line as './progressbar x y' where 'x' is a time in seconds and 'y' is a message to display. The inner function progressbar() works standalone as well and takes 'x' as a percentage and 'y' as a message.

#!/bin/bash

if [ "$#" -eq 0 ]; then echo "x is \"time in seconds\" and z is \"message\""; echo "Usage: progressbar x z"; exit; fi
progressbar() {
        local loca=$1; local loca2=$2;
        declare -a bgcolors; declare -a fgcolors;
        for i in {40..46} {100..106}; do
                bgcolors+=("$i")
        done
        for i in {30..36} {90..96}; do
                fgcolors+=("$i")
        done
        local u=$(( 50 - loca ));
        local y; local t;
        local z; z=$(printf '%*s' "$u");
        local w=$(( loca * 2 ));
        local bouncer=".oO°Oo.";
        for ((i=0;i<loca;i++)); do
                t="${bouncer:((i%${#bouncer})):1}"
                bgcolor="\\E[${bgcolors[RANDOM % 14]}m \\033[m"
                y+="$bgcolor";
        done
        fgcolor="\\E[${fgcolors[RANDOM % 14]}m"
        echo -ne " $fgcolor$t$y$z$fgcolor$t \\E[96m(\\E[36m$w%\\E[96m)\\E[92m $fgcolor$loca2\\033[m\r"
};
timeprogress() {
        local loca="$1"; local loca2="$2";
        loca=$(bc -l <<< scale=2\;"$loca/50")
        for i in {1..50}; do
                progressbar "$i" "$loca2";
                sleep "$loca";
        done
        echo -e "\n"
};
timeprogress "$1" "$2"