|This module implements a Haskell DNS Resolver on top of the
ADNS library. GHC users should compile their code using the
-threaded runtime system.
|type Resolver = String -> RRType -> [QueryFlag] -> IO (MVar Answer)|
|A Resolver is an IO computation which -- given the name
and type of the record to query -- returns an MVar that will
eventually contain the Answer from the Domain Name System.
|initResolver :: [InitFlag] -> (Resolver -> IO a) -> IO a|
|Run the given IO computation with an Initialized
Resolver. Note that resolver functions can be shared,
and should be shared between any number of IO
threads. You may use multiple resolvers, of course, but
doing so defeats the purpose of an asynchronous resolver.
|toPTR :: HostAddress -> String|
|Print an IP host address as a string suitable for PTR lookups.
|resolveA :: Resolver -> HostName -> IO (Either Status [HostAddress])|
|Resolve a hostname's A records.
|resolvePTR :: Resolver -> HostAddress -> IO (Either Status [HostName])|
|Get the PTR records assigned to a host address. Note
that although the API allows for a record to have more
than one PTR entry, this will actually not happen
because the GNU adns library can't handle this case and
will return sINCONSISTENT.
|resolveMX :: Resolver -> HostName -> IO (Either Status [(HostName, HostAddress)])|
|Resolve the mail exchangers for a hostname. The returned
list may contain more than one entry per hostname, in
case the host has several A records. The records are
returned in the order you should try to contact them as
determined by the priority in the RRMX response.
|query :: (Resolver -> a -> IO (Either Status [b])) -> Resolver -> a -> IO (Maybe [b])|
Convenience wrapper that will modify any of the
revolveXXX functions above to return Maybe rather
than Either. The idea is that Nothing signifies any
sort of failure: Just  signifies sNXDOMAIN or
sNODATA, and everything else signifies sOK.
So if you aren't interested in getting accurate Status
codes in case of failures. Wrap your DNS queries as
queryA :: Resolver -> HostName -> IO (Maybe [HostAddress])
queryA = query resolveA
|dummyDNS :: Resolver|
|Use this function to disable DNS resolving. It will
always return (Answer sSYSTEMFAIL Nothing (Just
host) (-1) ).
|Produced by Haddock version 0.8|