flush()
 Write data buffer to the data store
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 Prototype

     ERRCODE flush(
                       AREAP wa
                    )

 Arguments

     wa is a pointer to self.

 Description

     flush() writes active data and buffers to the work area's data store (usually a
     disk).

 Default Behavior

     You must implement the default behavior of this method through a
     subclass.

 Implementation Notes

     .  All implementations of flush() should perform a call to
        goCold() before physically updating the work area.

     .  Use writeDBHeader() to write the contents of the header record
        to disk.

 Files  Header file is Rdd.api.