Bash countdown help

Jsaba2 · 01-23-2013, 02:37 PM

So I have a script that is turning off some computers in my network and I have a countdown going, written like this:

echo "Shutting down all instructor machines";
echo "5...";
sleep 1;
echo "4...";
sleep 1;
echo "3...";
sleep 1;
echo "2...";
sleep 1;
echo "1...";
sleep 1;

echo "Waiting for machines to power down, please wait..."

network_admin -shutdown machine_list_instr

I am fully aware that this is a shitty way to do a countdown, is there a more, uh, elegant way to make this countdown?

bipinajith · 01-23-2013, 03:33 PM

Here is one way of doing it by using a while loop. I have also used \c to suppress trailing newline. You can remove if you don't want them.

Code:

#!/bin/bash
echo "Shutting down all instructor machines";
i=5
while [ $i -ge 0 ]
do
        [[ $i -ne 0 ]] && echo -e "${i}...\c";
        [[ $i -eq 0 ]] && echo -e "${i}\n"
        i=$(( i - 1 ))
        sleep 1
done

antegallya · 01-23-2013, 04:56 PM

Another flavor

Code:

#!/bin/sh
echo "Shutting down all instructor machines"
for i in $(seq 5 -1 1)
do
  echo -ne "$i...\r"
  sleep 1
done
echo "Waiting for machines to power down, please wait..."
network_admin -shutdown machine_list_instr

chrism01 · 01-23-2013, 07:12 PM

Code:

#!/bin/bash
echo "Shutting down all instructor machines";
for i in  {5..1}
do
    echo -n "$i ... "
    sleep 1
done
echo "Waiting for machines to power down, please wait..."
network_admin -shutdown machine_list_instr

unSpawn · 01-23-2013, 07:18 PM

Moved: This thread is more suitable in the Programming forum and has been moved accordingly to help your thread/question get the exposure it deserves.

konsolebox · 01-23-2013, 07:28 PM

Code:

#!/bin/bash

function countdown {
    local -i S=$1
    for (( ; S > 0; --S )); do
        echo "${S}..."
        sleep 1s  # read would do but it accepts input.
    done
}

echo "Shutting down all instructor machines.";
countdown 5
echo "Waiting for machines to power down, please wait..."
network_admin -shutdown machine_list_instr

bigearsbilly · 01-24-2013, 02:19 AM

here's mine:

Code:

countdown()
{
    (( $# > 0 )) || return
    count=$1
    while (( count ))
    do
        printf "\033[K\r$count"
        sleep 1
        (( count -- ))
    done
}

kooru · 01-24-2013, 03:34 AM

Code:

#!/bin/bash

echo "Shutting down all instructor machines"
i=5

while true
do
  echo "${i}.."
  sleep 1
  i=$(($i-1))

  if [[ $i -eq 0 ]]; then
          break
  fi

done

echo "Waiting for machines to power down, please wait..."

Jsaba2 · 01-24-2013, 06:58 AM

Oh wow, Thank you guys so much! Seeing all these different methods really shows me some options I have when working with shell script, you guys rule! Props all around!