The BUFFERCOUNT specifier indicates the number of buffers to be associated with the unit for multibuffered I/O. It takes the following form:
The BLOCKSIZE specifier determines the size of each buffer. For example, if BUFFERCOUNT=3 and BLOCKSIZE=2048, the total number of bytes allocated for buffers is 3*2048, or 6144 bytes.
If you do not specify BUFFERCOUNT or you specify zero for bc, the default is 1.
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