[tigershark]

It’s not true, plenty of DOS programs stopped I/O operations with ctrl + z, and exited with ctrl + c. What you are saying is that obviously there was no physical 1A byte to demarcate the end of the file, but 1A was used pretty much everywhere. And it’s actually a non printable character: https://en.m.wikipedia.org/wiki/Substitute_character So I’m missing the point of this article, CTRL Z and CTRL D are obviously non printable characters and of course they are not used anymore to demarcate the actual end of a file.