anecdotes:a.out_percolate
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Back around 1970-71, Unix on the PDP-11/20 ran on hardware that not only did not support virtual memory, but didn't support any kind of hardware memory mapping or protection, for example against writing over the kernel. This was a pain, because we were using the machine for multiple users. When anyone was working on a program, it was considered a courtesy to yell " | Back around 1970-71, Unix on the PDP-11/20 ran on hardware that not only did not support virtual memory, but didn't support any kind of hardware memory mapping or protection, for example against writing over the kernel. This was a pain, because we were using the machine for multiple users. When anyone was working on a program, it was considered a courtesy to yell " | ||
- | [A substory: at some point several were sitting around working away. Bob Morris asked, almost conversationally, | + | [A substory: at some point several were sitting around working away. Bob Morris asked, almost conversationally, |
We knew the PDP-11/45, which did support memory mapping and protection for the kernel and other processes, was coming, but not instantly; in anticipation, | We knew the PDP-11/45, which did support memory mapping and protection for the kernel and other processes, was coming, but not instantly; in anticipation, |
anecdotes/a.out_percolate.txt · Last modified: 2022/09/29 01:51 by 18.204.56.97