Video: C Programming on System 6 - Porting OpenBSD's diff(1)

posted on oct 28th, 2020 with tags mac, retrocomputing, and video
part of C Programming on System 6 series

I’ve wanted a simple revision control system on my Mac since starting development of my IMAP client. Porting a large system like Git or even CVS would be overkill (and very slow), but maybe something small like OpenBSD’s RCS implementation would suffice. For now, just having a diff utility would be helpful so in this video I port the guts of OpenBSD’s diff(1) and show it generating a unified diff between revisions of a C file.

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Video: C Programming on System 6 - Parsing RFC822 Dates

posted on oct 16th, 2020 with tags mac, retrocomputing, and video
part of C Programming on System 6 series

I wrote a utility function to parse RFC822 dates/times sent by the IMAP server, which then converts them to a UTC time. In this video, I hook it into the IMAP parser and add a resource string for the local timezone offset setting, so these UTC times can then be converted to a local time and displayed in the message list.

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Video: C Programming on System 6 - Intro

posted on oct 1st, 2020 with tags mac, retrocomputing, and video, and last updated on oct 20th, 2020
part of C Programming on System 6 series

I’ve been writing an IMAP client for and on my Mac 512Ke over the past many weeks. Taking inspiration from Andreas Kling’s excellent YouTube videos documenting his development of the Serenity operating system, I thought I’d start screencasting some of my work.

This video is the first of hopefully many and presents a quick introduction to System 6, HFS resource forks, THINK C 5.0, and a look at some of the progress of my IMAP client so far.

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Cidco MailStation as a Z80 Development Platform

posted on may 3rd, 2019 with tags hardware, retrocomputing, and z80, and last updated on mar 31st, 2020

The Cidco MailStation is a series of dedicated e-mail terminals sold in the 2000s as simple, standalone devices for people to use to send and receive e-mail over dialup modem. While their POP3 e-mail functionality is of little use today, the hardware is a neat Z80 development platform that integrates a 320x128 LCD, full QWERTY keyboard, and an internal modem.

After purchasing one (ok, four) on eBay some months ago, I’ve learned enough about the platform to write my own software that allows it to be a terminal for accessing BBSes via its modem or as a terminal for a Unix machine connected over parallel cable.

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Dolch PAC 64

posted on mar 20th, 2018 with tags hardware, and retrocomputing

The Dolch PAC 64 is a portable, rugged Pentium-powered PC from the mid 1990s. It was usually used (and can usually be found on eBay) as a “portable network sniffer” complete with multiple network cards supporting multiple media types.

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