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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In this episode, I fetch the flags of each message and for unseen messages, make them appear in the list in bold. That introduces an off-by-one which I run out of time to fix while recording.

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Today, I implement plaintext message viewing and hook it up to the message list. I also review a cleanup of int variables to make them either short or long throughout the project.

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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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I recently read about using a jump instruction as an LDEF resource to allow keeping the list definition function in the main program executable/project, so in this video I implement the technique for the message list.

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In this video, I get the list of messages displaying again and fix a bug that occurred when closing a mailbox. I provide a quick summary of creating LDEF procedures in THINK C for drawing custom list cells, which I will expand upon on in a future video.

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In this episode, I fix the off-by-one error in the IMAP envelope parser noted in the previous episode, then improve the tracking of a malloced buffer that gets shifted around during parsing.

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Returning to the development of my IMAP client, in this video I add functionality to fetch the default mailbox name from the resource file (later to be moved to a preferences window) and then eventually locate a crash in the IMAP protocol parser from a bogus memmove.

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In this video, I create a new GUI application from scratch, create a resource file and add an image to it, and then display that image in a window. I also cover using THINK C’s debugger to inspect a struct. Then, my Mac dies.

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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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Now that my Mac 512Ke is able to use PPP for native TCP/IP, I wanted an easy way to do PPP between it and an OpenBSD server on my network. I initially did this with a physical serial cable, but was later able to do it over TCP so I could retain the use of my WiFi232.

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I recently came across an unused Dove Computer MacSnap RAM upgrade on eBay, so I bought it and installed it in my Mac 512Ke to bring its RAM up to 1Mb.

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I used OpenBSD on the original Surface Go back in 2018 and many things worked with the big exception of the internal Atheros WiFi. This meant I had to keep it tethered to a USB-C dock for Ethernet or use a small USB-A WiFi dongle plugged into a less-than-small USB-A-to-USB-C adapter.

Microsoft has switched to Intel WiFi chips on their recent Surface devices, making the Surface Go 2 slightly more compatible with OpenBSD.

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Last year I wrote about the Cidco MailStation and how I was using it as a Z80 development platform. One of the biggest hurdles to running code on them is that it must be uploaded over the MailStation’s parallel port with a LapLink cable and some custom software (although it’s certainly easier than having to pull and flash a chip).

I recently created a USB data loader device that allows for easier development from a modern computer and implements the MailStation’s custom data encoding routines in its firmware.

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Back in 2017, I bought an Arduboy, a fun little Arduino development system which integrates an ATmega32U4 8-bit CPU, 32Kb of flash storage, 2Kb of RAM, a 128x64 pixel OLED display, some buttons, a speaker, and a battery in a Gameboy-like package.

OpenBSD had an old Arduino package available without the Arduino IDE, and it instead included a custom Makefile for end-users to build off of for compiling projects. But it was all pretty old and crufty and kind of sucked the fun out of tinkering with a new piece of hardware.

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