顯示進度 progress

範例：簡易版

echo -ne '>>>                       [20%]\r'
# some task
sleep 2
echo -ne '>>>>>>>                   [40%]\r'
# some task
sleep 2
echo -ne '>>>>>>>>>>>>>>            [60%]\r'
# some task
sleep 2
echo -ne '>>>>>>>>>>>>>>>>>>>>>>>   [80%]\r'
# some task
sleep 2
echo -ne '>>>>>>>>>>>>>>>>>>>>>>>>>>[100%]\r'
echo -ne '\n'

範例：顯示進度條顯示進度條1

#!/bin/bash
#
# inprogress.sh
# Description: this script may show some simple motion in foreground
# when main program in progress.
# Author: A-Lang (alang[dot]hsu[at]gmail[dot]com)

trap "kill $BG_PID;echo;exit" 1 2 3 15

function waiting
{
    INTERVAL=0.5
    TT='->——
    –>—–
    —>—-
    —->—
    —–>–
    ——>-
    ——->
    ——<-
    —–<–
    —-<—
    —<—-
    –<—–
    -<——
    <——-';
    echo -ne "Please waiting… \n"
    while true
    do
        for j in $TT
        do
            echo -ne "Please be patient, $j\r"
            sleep $INTERVAL
        done

    done
}

# Start the waiting, where place your main program.
waiting &
BG_PID=$!

sleep 10

# End of the waiting
kill $BG_PID
echo

範例：顯示進度條2

YT: Creating an Animated Progress Bar from scratch in Bash to batch-process files! - YouTube

#!/usr/bin/env bash

BATCHSIZE=1

progress-bar() {
	local current=$1
	local len=$2

	local bar_char='|'
	local empty_char=' '
	local length=50
	local perc_done=$((current * 100 / len))
	local num_bars=$((perc_done * length / 100))

	local i
	local s='['
	for ((i = 0; i < num_bars; i++)); do
		s+=$bar_char
	done
	for ((i = num_bars; i < length; i++)); do
		s+=$empty_char
	done
	s+=']'

	echo -ne "$s $current/$len ($perc_done%)\r"
}

process-files() {
	local files=("$@")

	sleep .01
}

shopt -s globstar nullglob

echo 'finding files'
files=(./**/*cache)
len=${#files[@]}
echo "found $len files"

for ((i = 0; i < len; i += BATCHSIZE)); do
	progress-bar "$((i+1))" "$len"
	process-files "${files[@]:i:BATCHSIZE}"
done
progress-bar "$len" "$len"

echo

旋轉符號

#!/usr/bin/env bash

spinner()
{
    local pid=$!
    local delay=${1:1}
    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"
    done
    printf "    \b\b\b\b"
}

# Run your program here
#(a_long_running_task) &
sleep 10 &
spinner 0.75

範例：整合 LED 的顯示

#!/bin/bash

echo "Starting to format the disk...."

# Start to blink the LED
/root/bin/led.sh b
/root/bin/led.sh blink &
led_pid=$!

# Main codes
echo "formating hdisk2..."
sleep 10

# When the main codes is ending up
# Stop to blink the LED
kill -9 $led_pid
wait $led_pid 2>/dev/null
sleep 2

# Making sure the LED is ON with Blue
/root/bin/led.sh b
echo "done"

led.sh 用來控制 LED 的閃燈

wait .... 這行用來隱藏 killed ... 的文字訊息