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ARES_PROCESS(3)       DragonFly Library Functions Manual       ARES_PROCESS(3)

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)