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3.2.47 gethostbyaddr

gethostbyaddr 

ADDR

, 

ADDRTYPE

This function does the same thing as gethostbyaddr (3): it translates a packed binary network address to its corresponding names (and alternate addresses). The return value in list context is:

($name, $aliases, $addrtype, $length, @addrs)

where @addrs is a list of packed binary addresses. In the Internet domain, each address is four bytes long, and can be unpacked by saying something like:

($a, $b, $c, $d) = unpack('C4', $addrs[0]);

In scalar context, gethostbyaddr returns only the host name. See the section on "Sockets" in Chapter 6 for another approach.