readat/writeat

[rennergade]

… call

Description

change read and write to use readat and writeat, removing excess seek call

Fixes # (issue)
Minor performance improvements

Type of change

• New feature (non-breaking change which adds functionality)

How Has This Been Tested?

Rust suite/lamp tests

[Yaxuan-w]

read_at and write_at will read data directly from the specified offset of the file. Change to use them will avoid using seek() and make the code more clear. The overall logic makes sense to me so approved.

[JustinCappos]

This is also quite confusing with readat calling read_at, etc. More comments about why you are doing what you are doing / code clarity would be a big help here.