When scripting in bash or any other shell in *NIX, while running a command that will take more than a few seconds, a progress bar is needed.
For example, copying a b
It may be achieved in a pretty simple way:
for
loop$bar
variable another =
sign to make the progress bar wider\r
cleans line and returns to the beginning of the line; -ne
makes echo
doesn't add newline at the end and parses \r
special character)function progress {
bar=''
for (( x=0; x <= 100; x++ )); do
sleep 0.25
bar="${bar}="
echo -ne "$bar ${x}%\r"
done
echo -e "\n"
}
$ progress
> ========== 10% # here: after 2.5 seconds
$ progress
> ============================== 30% # here: after 7.5 seconds
COLORED PROGRESS BAR
function progress {
bar=''
for (( x=0; x <= 100; x++ )); do
sleep 0.05
bar="${bar} "
echo -ne "\r"
echo -ne "\e[43m$bar\e[0m"
local left="$(( 100 - $x ))"
printf " %${left}s"
echo -n "${x}%"
done
echo -e "\n"
}
To make a progress bar colorful, you can use formatting escape sequence - here the progress bar is yellow: \e[43m
, then we reset custom settings with \e[0m
, otherwise it would affect further input even when the progress bar is done.
This is only applicable using gnome zenity. Zenity provides a great native interface to bash scripts: https://help.gnome.org/users/zenity/stable/
From Zenity Progress Bar Example:
#!/bin/sh
(
echo "10" ; sleep 1
echo "# Updating mail logs" ; sleep 1
echo "20" ; sleep 1
echo "# Resetting cron jobs" ; sleep 1
echo "50" ; sleep 1
echo "This line will just be ignored" ; sleep 1
echo "75" ; sleep 1
echo "# Rebooting system" ; sleep 1
echo "100" ; sleep 1
) |
zenity --progress \
--title="Update System Logs" \
--text="Scanning mail logs..." \
--percentage=0
if [ "$?" = -1 ] ; then
zenity --error \
--text="Update canceled."
fi
Using suggestions listed above, I decided to implement my own progress bar.
#!/usr/bin/env bash
main() {
for (( i = 0; i <= 100; i=$i + 1)); do
progress_bar "$i"
sleep 0.1;
done
progress_bar "done"
exit 0
}
progress_bar() {
if [ "$1" == "done" ]; then
spinner="X"
percent_done="100"
progress_message="Done!"
new_line="\n"
else
spinner='/-\|'
percent_done="${1:-0}"
progress_message="$percent_done %"
fi
percent_none="$(( 100 - $percent_done ))"
[ "$percent_done" -gt 0 ] && local done_bar="$(printf '#%.0s' $(seq -s ' ' 1 $percent_done))"
[ "$percent_none" -gt 0 ] && local none_bar="$(printf '~%.0s' $(seq -s ' ' 1 $percent_none))"
# print the progress bar to the screen
printf "\r Progress: [%s%s] %s %s${new_line}" \
"$done_bar" \
"$none_bar" \
"${spinner:x++%${#spinner}:1}" \
"$progress_message"
}
main "$@"
EDIT: For an updated version check my github page
I was not satisfied with the responses on this question. What I was personally looking for was a fancy progress bar as is seen by APT.
I had a look at the C source code for APT and decided to write my own equivalent for bash.
This progress bar will stay nicely at the bottom of the terminal and will not interfere with any output sent to the terminal.
Please do note that the bar is currently fixed at 100 characters wide. If you want scale it to the size of the terminal, this is fairly easy to accomplish as well (The updated version on my github page handles this well).
I will post my script here. Usage example:
source ./progress_bar.sh
echo "This is some output"
setup_scroll_area
sleep 1
echo "This is some output 2"
draw_progress_bar 10
sleep 1
echo "This is some output 3"
draw_progress_bar 50
sleep 1
echo "This is some output 4"
draw_progress_bar 90
sleep 1
echo "This is some output 5"
destroy_scroll_area
The script (I strongly recommend the version on my github instead):
#!/bin/bash
# This code was inspired by the open source C code of the APT progress bar
# http://bazaar.launchpad.net/~ubuntu-branches/ubuntu/trusty/apt/trusty/view/head:/apt-pkg/install-progress.cc#L233
#
# Usage:
# Source this script
# setup_scroll_area
# draw_progress_bar 10
# draw_progress_bar 90
# destroy_scroll_area
#
CODE_SAVE_CURSOR="\033[s"
CODE_RESTORE_CURSOR="\033[u"
CODE_CURSOR_IN_SCROLL_AREA="\033[1A"
COLOR_FG="\e[30m"
COLOR_BG="\e[42m"
RESTORE_FG="\e[39m"
RESTORE_BG="\e[49m"
function setup_scroll_area() {
lines=$(tput lines)
let lines=$lines-1
# Scroll down a bit to avoid visual glitch when the screen area shrinks by one row
echo -en "\n"
# Save cursor
echo -en "$CODE_SAVE_CURSOR"
# Set scroll region (this will place the cursor in the top left)
echo -en "\033[0;${lines}r"
# Restore cursor but ensure its inside the scrolling area
echo -en "$CODE_RESTORE_CURSOR"
echo -en "$CODE_CURSOR_IN_SCROLL_AREA"
# Start empty progress bar
draw_progress_bar 0
}
function destroy_scroll_area() {
lines=$(tput lines)
# Save cursor
echo -en "$CODE_SAVE_CURSOR"
# Set scroll region (this will place the cursor in the top left)
echo -en "\033[0;${lines}r"
# Restore cursor but ensure its inside the scrolling area
echo -en "$CODE_RESTORE_CURSOR"
echo -en "$CODE_CURSOR_IN_SCROLL_AREA"
# We are done so clear the scroll bar
clear_progress_bar
# Scroll down a bit to avoid visual glitch when the screen area grows by one row
echo -en "\n\n"
}
function draw_progress_bar() {
percentage=$1
lines=$(tput lines)
let lines=$lines
# Save cursor
echo -en "$CODE_SAVE_CURSOR"
# Move cursor position to last row
echo -en "\033[${lines};0f"
# Clear progress bar
tput el
# Draw progress bar
print_bar_text $percentage
# Restore cursor position
echo -en "$CODE_RESTORE_CURSOR"
}
function clear_progress_bar() {
lines=$(tput lines)
let lines=$lines
# Save cursor
echo -en "$CODE_SAVE_CURSOR"
# Move cursor position to last row
echo -en "\033[${lines};0f"
# clear progress bar
tput el
# Restore cursor position
echo -en "$CODE_RESTORE_CURSOR"
}
function print_bar_text() {
local percentage=$1
# Prepare progress bar
let remainder=100-$percentage
progress_bar=$(echo -ne "["; echo -en "${COLOR_FG}${COLOR_BG}"; printf_new "#" $percentage; echo -en "${RESTORE_FG}${RESTORE_BG}"; printf_new "." $remainder; echo -ne "]");
# Print progress bar
if [ $1 -gt 99 ]
then
echo -ne "${progress_bar}"
else
echo -ne "${progress_bar}"
fi
}
printf_new() {
str=$1
num=$2
v=$(printf "%-${num}s" "$str")
echo -ne "${v// /$str}"
}
#!/bin/bash
function progress_bar() {
bar=""
total=10
[[ -z $1 ]] && input=0 || input=${1}
x="##"
for i in `seq 1 10`; do
if [ $i -le $input ] ;then
bar=$bar$x
else
bar="$bar "
fi
done
#pct=$((200*$input/$total % 2 + 100*$input/$total))
pct=$(($input*10))
echo -ne "Progress : [ ${bar} ] (${pct}%) \r"
sleep 1
if [ $input -eq 10 ] ;then
echo -ne '\n'
fi
}
could create a function that draws this on a scale say 1-10 for the number of bars :
progress_bar 1
echo "doing something ..."
progress_bar 2
echo "doing something ..."
progress_bar 3
echo "doing something ..."
progress_bar 8
echo "doing something ..."
progress_bar 10
use the linux command pv:
http://linux.die.net/man/1/pv
it doesn't know the size if it's in the middle of the stream, but it gives a speed and total and from there you can figure out how long it should take and get feedback so you know it hasn't hung.