Possibly don't need to use connections with files that don't end with newlines

[jimhester]

If I am reading the POSIX spec correctly it allows you to mmap a file longer than the filename and guarantees the extra bytes until the next page will be zero padded. So you should be able to always mmap the file to file_size + 1 and guarantee it will end with a newline or zero byte.

https://unix.stackexchange.com/questions/616848/what-is-the-behaviour-of-a-file-backed-memory-map-when-reading-from-or-writing-t