Past exam of the year 1 of the computer science course of the University of Oxford / 2014 / Digital systems, linear algebra, introduction to formal proof / 2 / e / i / Solution

Each address uses $32/8=4$ bytes, so an address block holds $q=2048/4=512$ pointers. Use zero-based file offsets. The requested file offset hasThus select direct pointer index 1, read its file data block, and take the byte at offset 952 within it. No address block is needed:Fetching an uncached inode adds one read. If “byte 3000” instead uses one-based numbering, the within-block offset is 951; it is still the second file data block, with the same read count. Pathname lookup is separate from accessing a known inode.