Hi
I am trying to write something like this:
i need to find something in the output of a command and redirect that found line to a variable to i can call it somewhere else.

appreciate any help..


echo "please Enter the 1st 3rd Octet: "
read ipaddr

echo "Please Enter the number of host: "
read sub

for i in $(seq 1 $sub)
do
if ping -c 2 -t 2 $ipaddr.$i | grep "100.0% packet loss";
then echo "the host $ipaddr.$i is --- DOWN"
else echo "the host $ipaddr.$i is --- UP"
fi

nslkup=nslookup $ipaddr.$i | grep "name";
then echo "the $ipaddr.$i didnt resolve any name"
else echo "the $ipaddr.$i name is $nslkup "
fi
done

Hi,

welcome to LQ.

your sample code doesn't make sense to me but I guess you are looking for something like:
The above uses the date command to produce some output that is stored in the variable $foo.

HTH,

Evo2.

To capture a command's standard output you use command substituon like this:

output=$(command -arguments)
OR
output=`command -arguments`

The two forms are almost the same.
However you can also use the commands return value to check for success

ping -c 1 host

if [ $? -ne 0 ] ; then
# host wasn't pingeable
fi

or make grep silent and use its exit status only instead of its output, eg
use grep as a filter boolean tester.

ping -c 1 host | grep -q "100.0% packet loss"

if [ $? -eq 0 ]; then
# 100 % packet loss
fi


I hope this is clear.


Greetings,

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