836
votes

I have only found how to wait for user input. However, I only want to pause so that my while true doesn't crash my computer.

I tried pause(1), but it says -bash: syntax error near unexpected token '1'. How can it be done?

10

10 Answers

1468
votes

Use the sleep command.

Example:

sleep .5 # Waits 0.5 second.
sleep 5  # Waits 5 seconds.
sleep 5s # Waits 5 seconds.
sleep 5m # Waits 5 minutes.
sleep 5h # Waits 5 hours.
sleep 5d # Waits 5 days.

One can also employ decimals when specifying a time unit; e.g. sleep 1.5s

135
votes

And what about:

read -p "Press enter to continue"
77
votes

In Python (question was originally tagged Python) you need to import the time module

import time
time.sleep(1)

or

from time import sleep
sleep(1)

For shell script is is just

sleep 1

Which executes the sleep command. eg. /bin/sleep

43
votes

I realize that I'm a bit late with this, but you can also call sleep and pass the disired time in. For example, If I wanted to wait for 3 seconds I can do:

/bin/sleep 3

4 seconds would look like this:

/bin/sleep 4
43
votes

Run multiple sleeps and commands

sleep 5 && cd /var/www/html && git pull && sleep 3 && cd ..

This will wait for 5 seconds before executing the first script, then will sleep again for 3 seconds before it changes directory again.

37
votes

On Mac OSX, sleep does not take minutes/etc, only seconds. So for two minutes,

sleep 120
20
votes

Within the script you can add the following in between the actions you would like the pause. This will pause the routine for 5 seconds.

read -p "Pause Time 5 seconds" -t 5
read -p "Continuing in 5 Seconds...." -t 5
echo "Continuing ...."
10
votes

read -r -p "Wait 5 seconds or press any key to continue immediately" -t 5 -n 1 -s

To continue when you press any one button

for more info check read manpage ref 1, ref 2

2
votes

You can make it wait using $RANDOM, a default random number generator. In the below I am using 240 seconds. Hope that helps @

> WAIT_FOR_SECONDS=`/usr/bin/expr $RANDOM % 240` /bin/sleep
> $WAIT_FOR_SECONDS
2
votes

use trap to pause and check command line (in color using tput) before running it

trap 'tput setaf 1;tput bold;echo $BASH_COMMAND;read;tput init' DEBUG

press any key to continue

use with set -x to debug command line