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       ares_library_cleanup - c-ares library deinitialization


       #include <ares.h>

       void ares_library_cleanup(void)

       cc file.c -lcares


       The  ares_library_cleanup  function  uninitializes  the c-ares library,
       freeing all resources previously acquired by ares_library_init(3)  when
       the library was initialized.

       This  function  must  be  called  when the program using c-ares will no
       longer  need  any  c-ares  function.  Once  the  program   has   called
       ares_library_cleanup(3)  it  shall  not make any further call to any c-
       ares function.

       This function does not cancel any pending c-ares  lookups  or  requests
       previously done. Program  must use ares_cancel(3) for this purpose.

       This function is not thread safe.  You have to call it once the program
       is about to terminate, but this call must be done once the program  has
       terminated  every  single  thread that it could have initiated. This is
       required   to   avoid   potential   race    conditions    in    library
       deinitialization, and also due to the fact that ares_library_cleanup(3)
       might call functions from other libraries that are thread  unsafe,  and
       could  conflict with any other thread that is already using these other

       Win32/64 application DLLs shall not call  ares_library_cleanup(3)  from
       the  DllMain  function.  Doing  so  will  produce  deadlocks  and other


       This function was first introduced in c-ares version 1.7.0  along  with
       the  definition  of preprocessor symbol CARES_HAVE_ARES_LIBRARY_CLEANUP
       as an indication of the availability of this function.

       Since the introduction of this function, it is absolutely mandatory  to
       call it for any Win32/64 program using c-ares.

       Non-Win32/64 systems can still use c-ares version 1.7.0 without calling
       ares_library_cleanup(3) due to the fact that currently it is  nearly  a
       do-nothing function on non-Win32/64 platforms.


       ares_library_init(3), ares_cancel(3)


       Yang Tse

       Copyright 1998 by the Massachusetts Institute of Technology.
       Copyright (C) 2004-2009 by Daniel Stenberg.

                                  19 May 2009