mapped = blocksize/4 /* # of blks mapped by a single ptr blk */
Recall that for RECFM F a pointer to the next level block requires
4 bytes, but for RECFM V 12 bytes are needed (4 bytes for block
number, 4 bytes for last record for that block, 4 bytes for the
offset into that block). So, I think this "divide by 4" is too
simplistic.
Recall that RECFM V records require 2 additional bytes for the
length of the data in the record. So a record that contains
100 bytes of data is 102 bytes long.
Richard Corak
