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Questions tagged [vax]

For questions about DEC's VAX 32-bit minicomputers.

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18 votes
6 answers

How did the `long` and `short` integer types originate in C?

I was wondering why C has the long and short integer type in addition to the plain int, and came across the following quote in the C99 Rationale (thanks to this answer here): [...] In the 1970s, 16-...
9 votes
2 answers

Did VMS ever acquire filesystem cross-links?

Both Unix and Windows, quite early, acquired cross-links in their filesystems, such that the filesystems are not trees, but general directed graphs. I'm curious about whether this was an inevitable ...
8 votes
4 answers

VAX 11/780 16MB memory board - what was the physical size?

I'm trying to get a feel for what it looked like when you designed a computer to have a lot of memory chips stuffed into it. To that end, I found this:
11 votes
2 answers

Why did the VAX compatibility mode not implement the MARK instruction?

This question was inspired by an older question about the MARK instruction which recently bubbled up to the top of the active pile. The VAX-11/780 and several follow-on VAXen implemented a PDP-11 ...
7 votes
1 answer

Mainframe Hater's Handbook?

The famous The UNIX-HATERS Handbook claims this mailing list had been inspired by TWENEX-HATERS(1) and other *-LOVERS mailing lists, a long tradition of MIT. Moreover, the quote below implies there ...
3 votes
1 answer

Why did it take 2 hours to switch to a standby VAX? [closed]

According to this section of an excellent book on the history of Novell, I had actually started a business attempting to do some phases of what we are doing here at Novell. My plan was to develop to ...
10 votes
3 answers

Were the VAX eXtended Function Control (XFC) instructions ever used commercially?

The DEC VAX has a set of 256 instructions set aside for user addition via microcode edits. Were extension sets ever commercially produced and sold, or was this functionality mostly used in-house? ...
10 votes
2 answers

What did Richard Stallman have against VMS?

Richard Stallman of course was an advocate of free software, and VMS was proprietary, so he would've disapproved of it on that basis alone. (To be clear, I am not discussing here whether he was right ...
4 votes
2 answers

What random number generator was used in the VAX game Empire?

Around the year 1990, I played the game Empire on a VAX/VMS system. It was a turn-based, text-based-map wargame that later inspired Civilization and Xconq. What was particularly memorable about this ...
3 votes
1 answer

Porting of software from the m68k family architecture to the DEC VAX

I am looking for impressions, memoirs, articles, guidelines - everything that is possible about the unusual direction of software migration. I am interested in non-Unix related code, and preferably ...
3 votes
1 answer

DEC "CI" bus, better known as?

Looking over a list of various VAX processors, I noticed a reference to a "CI" bus. Poking about in Google I can only find very passing mentions of this, and no details. I suspect this had ...