Thanks all for the great input. I replaced line editing code for the time being with a one-liner to get the Unix input, and of course it works ok. I'll replace this with my own line editor some time later ;) Paul *Paul Riley* On Sun, 26 Jul 2020 at 09:10, Random832 wrote: > On Sat, Jul 25, 2020, at 11:31, Richard Salz wrote: > > Wasn't there an issue that v7 atty used stdin and BSD used stdout? > > v7 uses stdout, but system iii and v use stdin. oddly enough, later > research unix appears to unconditionally open /dev/tty, making the > redirection trick entirely unavailable. >