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#ifndef __com_sun_star_io_XAsyncOutputMonitor_idl__
#define __com_sun_star_io_XAsyncOutputMonitor_idl__

#include <com/sun/star/io/IOException.idl>
#include <com/sun/star/uno/XInterface.idl>

module com { module sun { module star { module io {

/**
   An optional companion interface to
   com::sun::star::io::XOutputStream that supports scenarios
   where com::sun::star::io::XOutputStream::writeBytes()
   operates asynchronously and does not necessarily report any errors.

   <p>A typical scenario where this interface is useful is when an
   com::sun::star::io::XOutputStream is used to write to a
   file via NFS.  Normally, any calls to
   com::sun::star::io::XOutputStream::writeBytes() will
   execute asynchronously then, in that any potential errors might only be
   reported by later calls to
   com::sun::star::io::XOutputStream::writeBytes() or
   com::sun::star::io::XOutputStream::closeOutput().  If
   such an output stream shall not be closed immediately after one or more calls
   to com::sun::star::io::XOutputStream::writeBytes(), but
   the client wants to know as soon as possible whether writing was successful,
   then
   com::sun::star::io::XAsyncOutputMonitor::waitForCompletion()
   should be called after the series of calls to
   com::sun::star::io::XOutputStream::writeBytes().</p>

   @since OOo 2.0
*/
interface XAsyncOutputMonitor {
    /**
       waits for the completion of any previous calls to
       com::sun::star::io::XOutputStream::writeBytes(),
       and reports potentially pending errors.

       <p>Calling this method is potentially expensive (even if the associated
       com::sun::star::io::XOutputStream represents a local
       file not accessed via NFS, for example).  This method has a similar
       description to
       com::sun::star::io::XOutputStream::flush().
       However, where the semantics of <code>flush</code> are rather vague,
       <code>waitForCompletion</code> has very specific semantics&mdash;it just
       blocks long enough so that any errors encountered during previous calls
       to com::sun::star::io::XOutputStream::writeBytes()
       can reliably be reported.  It specificially does not guarantee that any
       data have savely been stored on a stable physical medium, like a hard
       disk (and it is completely unspecified whether <code>flush</code> should
       give this guarantee).</p>

       @throws com::sun::star::io::IOException
       if any previous call to com::sun::star::io::XOutputStream::writeBytes()
       encountered such an error, but has not yet reported it (in cases where
       <code>writeBytes</code> operates asynchronously).
    */
    void waitForCompletion() raises (IOException);
};

}; }; }; };

#endif

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