Pertinent Detail

Demystifying “Ispell and its process have different character maps”
The ispell.el package for Emacs can issue the error message “Ispell and its process have different character maps”. It’s not clear from the message what this means. I explain what Emacs is thinking and, to give an example of how it can happen, I tell a war story of how I tripped over this.
How to filter calendar entries in Outlook Today
The Outlook Today display in Microsoft Outlook can be a convenient way of showing upcoming appointments in your calendar. But what if you don’t want to show all meetings. Outlook has no built in filtering but getting your hands dirty with a bit of Javascript can sort it all out.
ARM Instruction Formats/Timings
This is an introduction to opcode formats and timings for the ARM processor. It was written in conjunction with Robin Watts. It’s a little out of date now as it only deals with the ARM 2, 3 and 6 so doesn’t cover Thumb instructions but it’s not a bad place to start.
Sorting algorithms
This was a set of articles about sorting algorithms originally posted on comp.sys.acorn.programmer in September 1996 by Gareth McCaughan. I’ve made it available as it was too good to lose.
Integer square root and integer reciprocal square root routines for ARM processors.
These are two sets of articles which were posted on comp.sys.arm about how to calculate square root and reciprocal square root on ARM processors. These questions come up so frequently I thought I’d better put the answers somewhere safe.
Character sheets for Call of Cthulhu.
Printable character sheets for the Call of Cthulhu role-playing game.

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