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5.1 oskit_absio: Absolute I/O Interface

   

The oskit_absio interface supports reading from and writing to objects at specified absolute offsets, with no concept of a seek pointer. The oskit_absio interface is identical to the oskit_blkio COM interface, except that the block size is always one, since absolute IO is byte-oriented. In fact, an object that supports byte-granularity reads and writes can easily export both oskit_blkio and oskit_absio using exactly the same function pointer table, simply by implementing an oskit_blkio interface that always returns one from getblocksize, and then returning a pointer to that interface on queries for either oskit_blkio or oskit_absio.

The oskit_absio COM interface inherits from IUnknown, and has the following additional methods:

read
Read from this object, starting at the specified offset.
write
Write to this object, starting at the specified offset.
getsize
Get the current size of this object.
setsize
Set the current size of this object.





University of Utah Flux Research Group