Combining "read" and "while"

[TSch]

Hi folks,

another task ahead of me ...
Maybe you could give me a little idea about how to proceed.

I got a nice little monitoring script. Something like this (short version, just to make clear where the problem is):

clear
while [ 1 = 1 ];
do
arcstat=$(ps -ef | grep archiver | wc -l)
clear
case $arcstat in
 0) echo "Archiver NOT running !";;
 *) echo "Archiver running";;
esac
sleep 30
done

I keep the window containing the script active, running on screen of a monitoring PC.

Question is: Is it possible to modify the script, so that it would be possible to enter a command (e.g. restart the archiver, if it goes down) without having to interrupt the while statement ?

A first I thought of using functions somehow. Like this:

function checking
{
clear
while [ 1 = 1 ];
do
arcstat=$(ps -ef | grep archiver | wc -l)
clear
case $arcstat in
 0) echo "Archiver NOT running !";;
 *) echo "Archiver running";;
esac
sleep 2
done
}

function input
{
while [ 1 = 1 ];
do
read action
case $action in
 Q|q) kill $checkingpid
      ;;
   *) $action;;
esac
done
}

checking &
checkingpid=$!

input

But that's not it yet. It reads my Inputs, but keeps clearing them every 2 seconds, so I have to be extremely fast, which is quite impossible if I'm trying to enter longer commands. Increasing the sleep value wouldn't work either, because e.g. if I set it to 30 and accidently start entering the command after let's say 28 seconds I'm facing the same problem again. I need a way to separate the checking function from the input function ...
What am I missing ?
How else could I solve this problem ?

Regards,
Thomas

 

[feherke]

Hi

As you not specified your shell, I suppose that you are using [tt]bash[/tt].

[b]while[/b] [teal]:;[/teal] [b]do[/b]
  [b]if[/b] ps -ef [teal]|[/teal] grep -q [green][i]'archiver'[/i][/green][teal];[/teal] [b]then[/b]
    echo [green][i]"Archiver running"[/i][/green]
  [b]else[/b] 
    echo [green][i]"Archiver NOT running !"[/i][/green]
  fi

  [COLOR=chocolate]read[/color] -n [purple]1[/purple] -s -t [purple]30[/purple] char
  [b]case[/b] [green][i]"$char"[/i][/green] [b]in[/b]
    [green][i]'i'[/i][/green][teal])[/teal]
      [COLOR=chocolate]read[/color] -p [green][i]'enter command> '[/i][/green] action
      [b]case[/b] [green][i]"$action"[/i][/green] [b]in[/b]
        [teal]*)[/teal] echo [green][i]"processing command '$action'"[/i][/green]
      [b]esac[/b]
    [teal];;[/teal]
    [green][i]'q'[/i][/green][teal])[/teal] [COLOR=chocolate]break[/color] [teal];;[/teal]
  [b]esac[/b]
[b]done[/b]

What I am trying to show you is that you could do it in two steps :
[ul]
[li]First you hit a single character which starts interactive mode[/li]
[li]In interactive mode the looping is not working, so you can type looong commands easily[/li]
[/ul]


Feherke.

http://free.rootshell.be/~feherke/