But how can can i convert $QTYPE=23 to the hexa value of 2 octets which is '0023'

Wrong question.

You need to learn how to store 2316 into $QTYPE. Right now, you are storing 2310, a completely different number. 

$QTYPE = 0x23;  # 35

[download]

If you're starting with a string, you can use hex or oct. 

$QTYPE = hex('23');    # 35
$QTYPE = oct('0x23');  # 35

[download]

So is there any function in perl which directly convert the domain name into the required hexa format

There's no builtin function. I've specified the format (from which a solution is easily derived using split, length, and pack 'C') in an earlier post. Furthermore, someone gave you the name of a module that supposedly does the work for you.

In reply to Re^3: How to create a DNS message in perl? by ikegami
in thread How to create a DNS message in perl? by sanjay nayak

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