Chapter 15. Programming with the Resolver and Name Server Library Routines

"I know what you're thinking about," said Tweedledum; "but it isn't so, nohow."

"Contrariwise," continued Tweedledee, "if it was so, it might be; and if it were so, it would be; but as it isn't, it ain't. That's logic."

I bet you think resolver programming is hard. Contrariwise! It isn't very hard, really. The format of DNS messages is quite straightforward—you don't have to deal with ASN.1^[1] at all, as you do with SNMP. And you have nifty library routines to make parsing DNS messages easy. We've included portions of RFC 1035 in Appendix A. However, you might find it handy to have a copy of RFC 1035 to look at as we go through this chapter; at least have a copy of it nearby when you write your own DNS programs.

^[1] ASN.1 stands for Abstract Syntax Notation. ASN.1 is a method of encoding object types, accepted as an international standard by the International Organization for Standardization.