When did the sh shell provide intra-line editing?
I first experienced this with the CSH but maybe there were others before.
If I remember correctly traditionally there were the kill and erase
(#, @) characters, later on Berkeley added thinks like ^W (rub out
last word) and similar stuff. This was all handle by the terminal
driver in the kernel (saved context switches). Later people started
to move the edit operations to the CLI applications and libraries
like "readline", the terminal driver runs in cbreak (or whatever
it was called) mode.
jaap