plucky (3) ares_getsock.3.gz

NAME

       ares_getsock - get socket descriptors to wait on (deprecated)

SYNOPSIS

       #include <ares.h>

       int ares_getsock(const ares_channel_t *channel, ares_socket_t *socks,
                        int numsocks);

DESCRIPTION

       The  ares_getsock  function  retrieves the set of socket descriptors which the calling application should
       wait on for reading and/or writing for the processing of name service queries pending on the name service
       channel  identified by channel.  Socket descriptors will be set in the socket descriptor array pointed to
       by socks.  numsocks is the size of the given array in number of ints.

       This function can only return information up to 16 sockets. If more are  in  use,  they  are  simply  not
       reported back.

RETURN VALUES

       ares_getsock  returns  a bitmask for what actions to wait for on the different sockets. The ares.h header
       file provides these convenience macros to extract the information appropriately:

       #define ARES_GETSOCK_MAXNUM 16 /* ares_getsock() can return info about
                                         this many sockets */
       #define ARES_GETSOCK_READABLE(bits,num) (bits & (1<< (num)))
       #define ARES_GETSOCK_WRITABLE(bits,num) (bits & (1 << ((num) +                                          ARES_GETSOCK_MAXNUM)))

NOTES

       This function was added in c-ares 1.3.1 and deprecated in c-ares 1.20.0  due  to  the  implementation  of
       ARES_OPT_MAX_UDP_QUERIES which makes it likely to exceed 16 open file descriptors.

       It  is  recommended  to  use  ARES_OPT_EVENT_THREAD passed to ares_init_options(3) or to use socket state
       callbacks (ARES_OPT_SOCK_STATE_CB) registered via ares_init_options(3).

SEE ALSO

       ares_init_options(3), ares_timeout(3), ares_fds(3), ares_process(3)

                                                  11 March 2010                                  ARES_GETSOCK(3)