https://blog.jchw.io/ A blog about software. en https://blog.jchw.io/grantpt/ What exactly does the grantpt() function do on Linux? The answer may surprise you. Tue, 30 Dec 2025 13:10:00 +0000 John https://blog.jchw.io/grantpt/ https://blog.jchw.io/object-files-history/ A brief exploration into the history of object file formats. Wed, 11 Jun 2025 01:20:00 +0000 John https://blog.jchw.io/object-files-history/ https://blog.jchw.io/stealth-branches/ Code review and test line coverage often collude to try to force you to handle edge cases, but outsmarting both of those filters at once is sometimes easier than it seems. Fri, 05 Jul 2024 15:00:00 +0000 John https://blog.jchw.io/stealth-branches/ https://blog.jchw.io/who-is-resolving-my-names/ Be careful when isolating traffic using network namespaces: you might be surprised to see how difficult it is to ensure that there are absolutely no leaks. This post is about a surprise leak caused by nscd. Mon, 09 Oct 2023 00:57:52 +0000 John 652339f0837f8d010731bc0b https://blog.jchw.io/sending-at-commands-on-a-pixel-4a/ AT phone modem commands have existed since the early 1980s; here's how one can issue them on a typical Android phone decades later. Wed, 30 Aug 2023 23:00:00 +0000 John 64ef6e97837f8d010731bb62 https://blog.jchw.io/vs-code-with-flakes/ Nix flakes and Visual Studio Code can be a little cumbersome to work with together. Here is an approach to running isolated Visual Studio Code instances inside of Nix flake development shells. Sat, 06 May 2023 19:38:14 +0000 John 6456a09ae2671d02108d33c5 https://blog.jchw.io/triforce-bs1/ The Triforce arcade machine contains a nearly-stock GameCube motherboard in it, with essentially the only difference being the bootrom. This is a step-by-step reading of the first stage of the Triforce bootrom. Fri, 02 Sep 2022 05:08:48 +0000 John 630dae68c852fe020bc53263 https://blog.jchw.io/triforce-type-3-teardown/ The Triforce was a Nintendo GameCube-based arcade machine. Here's a complete teardown of the guts of the Triforce. Sat, 13 Aug 2022 20:36:08 +0000 John 62f7f6194c42ce020b320c4a https://blog.jchw.io/wrong-number/ When a friend of mine was developing some software, they were puzzled to find their software worked on Windows but crashed under Wine. A quirk of the MinGW toolchain and the behavior of the Windows loader led to a surprisingly subtle failure mode. Tue, 12 Apr 2022 13:00:00 +0000 John 6270732da79364020c23163a