How to create a 3 second timer in Bash?

Question

I created a task manager for linux with shell script I need to refresh the task manager every 3 seconds I was thinking of using Timer function but got stuck

I have these functions written:

getnum
print_form
printinfo
move_user_cursor

I got these functions in to a main function such as:

init() {
 getnum
 clear
 print_form
 printinfo
 move_user_cursor
}

and my script ends like this:

init

while true:
 do
  :
done

How can I make my script get refreshed every 3 seconds?

init(){
  getnum
  clear
  print_form
  printinfo
  move_user_cursor
}

init
while true;
do
  :
done

I expect Timer function, or sleep command

You want this to happen asynchronously, without ending the `while true` loop? — Barmar, May 14 '19 at 16:47
Is `:` a placeholder in your `while` loop, or is it really a loop that does nothing? — Barmar, May 14 '19 at 16:47
Possible duplicate of [How to include a timer in Bash Scripting?](https://stackoverflow.com/q/1226094/608639), [Run command every second in Bash?](https://stackoverflow.com/q/9299704/608639), [Repeat a Unix command every x seconds forever](https://unix.stackexchange.com/q/10646), [Repeat a command every x interval of time in terminal?](https://askubuntu.com/q/430382), [Repeat command automatically in Linux](https://stackoverflow.com/q/13593771/608639), etc. — jww, May 14 '19 at 17:32

score 2 · Answer 1 · answered May 14 '19 at 16:51

2

Replace

init
while true;
do
  :
done

with

while true;
do
  init
  sleep 3s
done

answered May 14 '19 at 16:51

Cyrus

84,225
14
89
153

I don't know why but it doensn't work – K.Paul May 14 '19 at 17:32

How to create a 3 second timer in Bash?

1 Answers1