The Origins of Malloc
The 1973 Fourth Edition Unix kernel source code contains two routines, malloc and mfree, that manage the dynamic allocation and release of main memory blocks for in-memory processes and of continuous disk swap area blocks for swapped-out processes. Their implementation and history can teach us many things regarding modern computing.
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The 1980s Research Unix Editions Are Now Available for Study
In 2002 Caldera International licensed the source code distribution of several historic Unix editions. This included all Research Unix editions up to the Seventh Edition, but excluded the 1980s 8th, 9th, and 10th Edition. This was unfortunate, because these editions pioneered or implemented several features that were very advanced at the time, such as streams inter-process communication, graphics terminals and the associated Sam text editor, network filesystems, and graphics typesetting tools.
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Measures of Donald Trump's Inaugural Address
Computers allow us to measure objectively the properties of text. I applied some established text and sentiment analysis algorithms on Donald Trump's inaugural address and compared the results with the same metrics of past well-known presidents. Presidential speeches are nowadays typically a team effort. Nevertheless, I thought that the speech writing team's output reflects the president's choices regarding staffing, policy, and style. Moreover, as luck would have it, in this case it was reported that Donald Trump wrote the inaugural address himself. The findings of this exercise surprised me.
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Raspberry Pi Zero vs Elliott 405
Raspberry Pi Zero
juxtaposed in front of the Norwich City Council Treasurer's Department building,
where the delivery of the Elliott 405 computer was photographed in 1957.
Here is how the two computers compare.
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The Birth of Standard Error
Earlier today Stephen Johnson, in a mailing list run by the
The Unix Heritage Society,
described the birth of the standard error concept:
the idea that a program's error output is sent on a channel
different from that of its normal output.
Over the past forty years, all major operating systems and language libraries
have embraced this concept.
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