3 ms·
I'm really starting to like this blog. If you're wondering why V7, it was the first portable UNIX and the last public Bell Labs distribution. It's free softwar
by guerrilla 5y ago
I'm really starting to like this blog.
If you're wondering why V7, it was the first portable UNIX and the last public Bell Labs distribution. It's free software now. V6 is the one for which the first BSD was a supplement for and that goes with Lion's commentary and was partially rewritten as xv6. PWB/UNIX, which eventually evolved into Syatem V, also derived from V6. So in a sense V6 is the first portable public common ancestor and V7 is the last.
- Taniwha 5y agoTo be fair v6 was able to be ported, it just wasn't as easy (I know because I ported it to native VAX) the compiler was the hard part, along with the evil context switch primitives
- msla 5y ago> along with the evil context switch primitives But you weren't expected to understand them! ;) Here's your own words now: https://news.ycombinator.com/item?id=24853698 https://news.ycombinator.com/item?id=24853698 dmr himself on the subject: https://www.bell-labs.com/usr/dmr/www/odd.html https://www.bell-labs.com/usr/dmr/www/odd.html
- Taniwha 5y agoThat comment is only partially related to those primitives - the primitives are used in a bunch of other places with more obvious functionality - it's the doing something strange because the SSWAP is set that you're not supposed to understand - where that bit is set is miles away and not obviously connected (plus there's that "return(1)" from a routine that no one who appears to call it uses the result). V7's save()/restore() are more portable and easier to understand