Filling an array not all at once

[TSch]

Hello everyone,

using ksh so far I know that if I would like to fill an Array I can e.G. use something like this:

set -A arrayname $(cat file)
set -A arrayname $(some command)

But what if I do not wish to fill the Array all at once ?

Let's say I have a list of Servers. Now I ping each one and only if the ping fails the Name of the Server shall be inserted into an Array.

What's an elegant way of doing it ?

Regards,
Thomas

 

[feherke]

Hi

Not sure if I understand your intentions correctly, as my solution has nothing to do with your posted code.
This is how I would solve such task :

[b]while read[/b] ip[teal];[/teal] [b]do[/b] ping -c [purple]3[/purple] -w [purple]6[/purple] [i][green]"$ip"[/green][/i] [teal]||[/teal] arrayname[teal]+=([/teal] [i][green]"$ip"[/green][/i] [teal]);[/teal] [b]done[/b] [teal]<[/teal] ip[teal].[/teal]txt

Feherke.
feherke.ga

 

[TSch]

Hi feherke,

sorry, here's a little bit more Detail:

I'm using the following command to generate a list (Array) of remote Printers:

set -A prtlst $(enq -isWA | awk '{print $1}' | grep -v " " | grep -v QUEUED | grep -v Queue | grep -v '\-----')

Next Comes the ping of each Print Server:

numbprt=$(echo ${prtlst[*]} | wc -w)

counter=0

while [ $counter -lt $numbprt ];
do
ping -c 4 ${prtlst[$counter]} > /dev/null 2> /dev/null
if [ $? -eq 0 ];
then
echo "${prtlst[$counter]} is reachable"
else
echo "${prtlst[$counter]} is NOT reachable"
fi
counter=`expr $counter + 1`
done

So what I'd like to do now is to create and to append to an additional Array if a Printer of $prtlst is not responding to the ping.

I don't like using external files like this:

echo ${prtlst[$counter]} >> unresponsive_prt.txt

Regards,
Thomas

 

[feherke]

Hi

Oops. When I read that "I have a list of Servers" for some reason I had the feeling you are talking about a file. I agree, neither I like to use temporary files when not necessary.

Anyway, to loop over the prtlst array and add each unresponsive one to a separate array, the basics are the same :

[b]set[/b] -A prtlst [navy]$([/navy]enq -isWA [teal]|[/teal] awk [i][green]'{print $1}'[/green][/i] [teal]|[/teal] grep -v [i][green]" "[/green][/i] [teal]|[/teal] grep -v QUEUED [teal]|[/teal] grep -v Queue [teal]|[/teal] grep -v [i][green]'[/green][/i][lime]\-[/lime][i][green]----'[/green][/i][teal])[/teal] 
[b]set[/b] -A unresponsive

[b]for[/b] server [b]in[/b] [i][green]"${prtlst[@]}"[/green][/i]
[b]do[/b]
    ping -c [purple]4[/purple] [i][green]"$server"[/green][/i] [teal]>[/teal] /dev/null [purple]2[/purple][teal]>[/teal] /dev/null
    [b]if[/b] [teal][[/teal] [navy]$?[/navy] -eq [purple]0[/purple] [teal]][/teal]
    [b]then[/b]
        echo [i][green]"$server is reachable"[/green][/i]
    [b]else[/b]
        echo [i][green]"$server is NOT reachable"[/green][/i]
        unresponsive[teal]+= ([/teal] [i][green]"$server"[/green][/i] [teal])[/teal]
    [b]fi[/b]
[b]done[/b]

echo [i][green]"From ${#prtlst[@]} servers the following ${#unresponsive[@]} are unresponsive : ${unresponsive[@]}"[/green][/i]

[small][maroon]Warning ![/maroon] The above code was tested only as separate pieces.[/small]

Note that if your [tt]ping[/tt] supports some kind of timeout option, I suggest to use it. ( If not available, the GNU coreutils package contains a [tt]timeout[/tt] tool to run commands only for certain time, but I am afraid that will not be available either on your system. )

Feherke.
feherke.ga