Tools.h++ Manual

104011 Tandem Computers Incorporated 21-51
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Public constructor RWCacheManager(RWFile* file, unsigned blocksz, unsigned
mxblks = 10);
Construct a cache for the RWFile pointed to by file . The length of the fixed-
size blocks is given by blocksz . The number of cached blocks is given by
mxblks .
~RWCacheManager();
Performs any pending I/O operations (i.e., calls flush() ) and deallocates any
allocated memory.
Public member functions RWBoolean flush();
Perform any pending I/O operations. Returns TRUE if the flush was
successful, FALSE otherwise.
void invalidate();
Invalidate the cache.
RWBoolean read(RWoffset locn, void* dat);
Return the data located at offset locn of the associated RWFile . The data is
put in the buffer pointed to by dat . This buffer must be at least as long as the
block size specified when the cache was constructed. Returns TRUE if the
operation was successful, otherwise FALSE .
RWBoolean write(RWoffset locn, void* dat);
Write the block of data pointed to by dat to the offset locn of the associated
RWFile . The number of bytes written is given by the block size specified
when the cache was constructed. The actual write to disk may be deferred.
Use member function flush() to perform any pending output. Returns TRUE
if the operation was successful, otherwise FALSE .