If the purpose of the conversion is to prepare an operand for a socket call, the dotted decimal ip notation must be converted to a packed 32 bit integer. For example, Perl's gethostbyaddress expects addresses in this format.

use Socket;
$ipaddr = inet_aton(127.0.0.1);

# In Perl 5.6 you can convert with the v-string notation:
# $ipaddr = v127.0.0.1;
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Off the back of the third camel, page 720.
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