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vincix

05-27-2015 06:44 AM

basic bash script

Code:

PREFIX=192.168.1

OCTET=1

while [ $OCTET -lt "255" ]; do

    echo -en "Pinging ${PREFIX}.${OCTET}..."

    ping -c1 -w1 ${PREFIX}.${OCTET} > /dev/null 2>&1

    if [ "$?" -eq "0" ]; then

      echo "OK"

    else

      echo "Failed"

    fi

    let OCTET=$OCTET+1

done

My question is, in the penultimate line, why is it OCTET, and not $OCTET, with a dollar before it, meaning, the variable?

What if it were written:

Code:

let $OCTET=$OCTET+1

Like in C++ (I think) or Python or whatever?

veerain

05-27-2015 06:48 AM

Read man page of bash.

In shell every variable is referenced without '$'. Only if you want the value of a variable '$' is used.

And it is designed so.

vincix

05-27-2015 07:07 AM

Thanks

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