POSIX の定義では『テキストファイル』はファイル末尾に改行が必要
3.392 Text File
A file that contains characters organized into one or more lines. https://pubs.opengroup.org/onlinepubs/000095399/basedefs/xbd_chap03.html#tag_03_392
3.205 Line
A sequence of zero or more non-
A file that contains characters organized into one or more lines. https://pubs.opengroup.org/onlinepubs/000095399/basedefs/xbd_chap03.html#tag_03_392
A sequence of zero or more non-