Crate c_ares[−][src]
Expand description
A safe wrapper for the c-ares library.
This crate is a fairly faithful wrapper of c-ares; which is to say that it preserves some of
the complexity of using the underlying library. If you just want to make a DNS query, you
should probably prefer the c-ares-resolver crate,
which does the hard work for you.
Direct usage of this crate requires you to pay attention to c-ares as it tells you which
file descriptors it cares about, and to poll for activity on those file descriptors.
This likely requires you to have an event loop or similar with which to integrate.
Still here? Usage of this crate is as follows:
-
Create a
Channel. -
Make queries on the
Channel. Queries all take callbacks, which will be called when the query completes. -
Have
c-arestell you what file descriptors to listen on for read and / or write events. You can do this either by providing a callback, which is called whenever the set of interesting file descriptors changes, or by querying theChanneldirectly either withget_sock()or withfds(). -
Do as
c-aresasks. That is, listen for the events that it requests, on the file descriptors that it cares about. -
When a file descriptor becomes readable or writable, call either
process_fd()orprocess()on theChannelto tellc-areswhat has happened. -
If you have queries pending and don’t see events happening, you still need to call either
process_fd()orprocess()at some point anyway - to givec-aresan opportunity to process any requests that have timed out.
Complete examples showing how to use the library can be found here.
Structs
The contents of a single AAAA record.
The result of a successful AAAA lookup.
Iterator of AAAAResults.
The contents of a single A record.
The result of a successful A lookup.
Iterator of AResults.
The contents of a single CAA record.
The result of a successful CAA lookup.
Iterator of CAAResults.
The result of a successful CNAME lookup.
A channel for name service lookups.
Flags that may be passed when initializing a Channel.
Information about the set of sockets that c-ares is interested in, as returned by
get_sock().
Iterator for sockets of interest to c-ares.
Iterator of IpAddrs.
Iterator of &'a CStrs.
The result of a successful host lookup.
The contents of a single MX record.
The result of a successful MX lookup.
Iterator of MXResults.
The contents of a single NAPTR record.
The result of a successful NAPTR lookup.
Iterator of NAPTRResults.
Flags that may be provided on a call to get_name_info().
The result of a successful NS lookup.
The result of a successful name-info lookup.
Used to configure the behaviour of the name resolver.
The result of a successful PTR lookup.
The result of a successful SOA lookup.
The contents of a single SRV record.
The result of a successful SRV lookup.
Iterator of SRVResults.
The contents of a single TXT record.
The result of a successful TXT lookup.
Iterator of TXTResults.
The contents of a single URI record.
The result of a successful URI lookup.
Iterator of URIResults.
Enums
Address families.
Error codes that the library might return.
Constants
An invalid socket / file descriptor. Use this to represent ‘no action’ when calling
process_fd() on a channel.
Functions
Get the version number of the underlying c-ares library.