NAME

       ares_process - Process events for name resolution

SYNOPSIS

       #include <ares.h>

       void ares_process(ares_channel channel, fd_set *read_fds,
       fd_set *write_fds)

       void ares_process_fd(ares_channel channel, ares_socket_t read_fd, ares_socket_t write_fd)

DESCRIPTION

       The  ares_process(3)  function  handles  input/output  events and timeouts associated with
       queries pending on the name service channel identified by channel.   The  file  descriptor
       sets  pointed  to  by  read_fds  and  write_fds  should  have file descriptors set in them
       according to whether the file descriptors specified by ares_fds(3) are ready  for  reading
       and  writing.   (The  easiest way to determine this information is to invoke select with a
       timeout no greater than the timeout given by ares_timeout(3) ).

       The ares_process function will invoke callbacks  for  pending  queries  if  they  complete
       successfully or fail.

       ares_process_fd(3)  works  the  same  way  but acts and operates only on the specific file
       descriptors (sockets) you pass in to the function. Use ARES_SOCKET_BAD  for  "no  action".
       This  function  is  of  course provided to allow users of c-ares to void select() in their
       applications and within c-ares.

   EXAMPLE
       The following code fragment waits for all pending queries on a channel to complete:

              int nfds, count;
              fd_set readers, writers;
              struct timeval tv, *tvp;

              while (1)
                {
                  FD_ZERO(&readers);
                  FD_ZERO(&writers);
                  nfds = ares_fds(channel, &readers, &writers);
                  if (nfds == 0)
                    break;
                  tvp = ares_timeout(channel, NULL, &tv);
                  count = select(nfds, &readers, &writers, NULL, tvp);
                  ares_process(channel, &readers, &writers);
                }

SEE ALSO

       ares_fds(3), ares_timeout(3)

AUTHOR

       Greg Hudson, MIT Information Systems
       Copyright 1998 by the Massachusetts Institute of Technology.

                                           25 July 1998                           ARES_PROCESS(3)