File I need to modify contains the following:
block: 16, size: 16, start: 8, length: 4
I'd like the file so that values for block, size will be divided by 2 while values for start, length will be multiplied by 2.
Since I have to make such modifications for a whole bunch of files, I am considering using Sed to do the substitution work for me. But I'm not sure calculations are allowed in the matching and substituting process.