mirror of
https://github.com/moparisthebest/curl
synced 2024-11-18 07:25:14 -05:00
47 lines
2.3 KiB
Plaintext
47 lines
2.3 KiB
Plaintext
This is c-ares, a forked version of the original ares. The original ares
|
|
README follows below, the c-ares specific details are in README.cares
|
|
|
|
====================================================================
|
|
|
|
This is ares, an asynchronous resolver library. It is intended for
|
|
applications which need to perform DNS queries without blocking, or
|
|
need to perform multiple DNS queries in parallel. The primary
|
|
examples of such applications are servers which communicate with
|
|
multiple clients and programs with graphical user interfaces.
|
|
|
|
This library implementation is not especially portable to crufty old
|
|
systems like SunOS 4. It assumes a compiler which can handle ANSI C
|
|
syntax, a system malloc which properly handles realloc(NULL, foo) and
|
|
free(NULL), and a reasonably up-to-date <arpa/nameser.h>.
|
|
|
|
I have attempted to preserve the externally visible behavior of the
|
|
BIND resolver in nearly all respects. The API of the library is, of
|
|
course, very different from the synchronous BIND API; instead of
|
|
invoking a function like res_send() and getting a return value back
|
|
indicating the number of bytes in the response, you invoke a function
|
|
like ares_send() and give it a callback function to invoke when the
|
|
response arrives. You then have to select() on the file descriptors
|
|
indicated by ares_fds(), with a timeout given by ares_timeout(). You
|
|
call ares_process() when select() returns.
|
|
|
|
Some features are missing from the current version of ares, relative
|
|
to the BIND resolver:
|
|
|
|
* There is no IPV6 support. [not true for c-ares]
|
|
* There is no hostname verification.
|
|
* There is no logging of unexpected events.
|
|
* There is no debugging-oriented logging.
|
|
* There is no YP support.
|
|
|
|
libares requires an ANSI compiler to compile and use. To build the
|
|
library, just run "./configure" and "make". To install it, run "make
|
|
install". Run "./configure --help" to see a list of options you can
|
|
provide to configure to change how the library builds. libares has no
|
|
data files, so you can move the include file and library around freely
|
|
without leaving behind any dependencies on old paths. Building the
|
|
library will also build the "adig" program, a little toy for trying
|
|
out the library. It doesn't get installed.
|
|
|
|
libares is distributed at athena-dist.mit.edu:pub/ATHENA/ares. Please
|
|
send bug reports and comments to ghudson@mit.edu.
|