The strategy that is used by the original GNU coreutils written in C, and the one I used to implement tail with Rust, is to jump to the end of the file, than re

The strategy that is used by the original GNU coreutils written in C, and the one I used to implement tail with Rust, is to jump to the end of the file, than rewind AVERAGE_CHARS_PER_LINE * NUMBER_OF_LINES_TO_BE_READ, check if enough lines have been read, and repeat until enough lines have been found. I found the optimal value of AVERAGE_CHARS_PER_LINE to be around 40 characters, but of course it hugely depends on the file being read.