Re: [TUHS] screen editors

It's interesting how much of this has  been lost to history. Curses, in particular, is sketchily documented, and se is unknown. Here's how I remember it. Bill Joy made major enhancements to previously enhanced versions of ed, creating vi. In 1979, he bumped up against the 64K boundary on the PDP-11, and handed it off to me. I made some more smaller enhancements. vi was huge by the standards of the day, especially compared to ed. There were ifdefs to take out several features, such as support for upper case only terminals, to make it fit on the PDP-11. I had to split it into version 2 (16 bit) and 3 (32 bit) to be able to enhance it and still support 2BSD on the PDP-11. Ken Arnold took the screen updating code from vi (just the "full screen update", not the parts that did insert/delete line/char) and turned it into the curses library. Rogue was the primary user of curses. Once I graduated from Berkeley went to Bell Labs, I took vi, termcap, and curses with me. I replaced termcap, which was too slow to start up (it was quadratic on the size of the entry, which was awful on the hardware of the day) with terminfo, a binary version that was faster. It included tools like tic and infocmp to translate back and forth to text and termcap. I also rewrote curses with a new algorithm that fully utilized insert/delete line/char. I had a paper to publish on the subject, but I lost it and never did publish it. I gave a talk at Usenix Boston in 1982 about the new curses and terminfo. But I couldn't release the code, because it was considered proprietary. Pavel Curtis offered to clone it, and I coached him on the algorithm and specs, and he released a good clone pcurses. Eventually that became ncurses. Nearly everyone at Bell Labs (outside area 11) was using either vi or emacs, but System III just had ed. There was a big push to add vi or emacs to UNIX 3.0 (System III), but USG instead chose to write se, the "screen editor" and put it in UNIX 4.0. Nobody would use it, so UNIX 5.0 (System V) relented and included vi.     Mary Ann On 1/7/20 8:30 AM, arnold(a)skeeve.com wrote: