macOS 13.0.0 Ventura introduced an irritating problem for all us Mac-based Raspberry Pi Pico programmers: Finder no longer allows you to copy .uf2
files to a mounted Pico. It’s not a forbidden operation, but it does trigger an error that prevents the copy from taking place. This is undoubtedly the ‘new normal’, so here are some ways to circumvent the error. I’ll save the best one until last.
Tag Archives: cli
How to talk to I2C sensors, displays from… Linux
T’other week, I wrote about my work on building a Raspberry Pi RP2040-based I²C host device and some macOS client software to control it. I mentioned that I might get the latter running under Linux too. I now have, and it does.
Continue readingHow to talk to I2C sensors, displays from a Mac
This post was originally going to be about building a tool to access I²C devices on a Mac, reaching them via USB and an Excamera Labs I2CMini adaptor board. But then I accidentally snapped the pins and board traces off my I2CMini, so I had to go back to the drawing board. Now it’s about accessing I²C devices on a Mac using a Raspberry Pi Pico, or any other RP2040-based board, as the adaptor.
Continue readingHow to manage multiple serial devices on a Mac
I connect to my Mac many USB devices that communicate over a serial (UART) bus to send debug information to the host or to receive data and code. You know, Raspberry Pi Picos, Adafruit Feathers, FTDI cables — that kind of thing. Often I have more than one connected. Is there an easy way to see what’s connected without listing /dev
every time and to remember connected devices’ paths?

Notarise macOS command line apps more quickly
It’s June once more, and time for Apple’s Worldwide Developers’ Conference (WWDC). This is a chance to learn about new functionality and, yes, discover initiatives announced at previous WWDCs that you completely missed the first time around. A case in point: Apple’s revamp of how apps are notarised at the command line, which was revealed at WWDC 21 but I only encountered this week.
Continue readingHow to write Unix man pages for macOS command line apps
Over the last few years I’ve released a number of command line utilities for macOS. I’ve always included online help within them, triggered with the --help
switch, but I recently wondered how I might provide Unix Manual pages too. It would allow users to call up help with the CLI command man
as well as a command switch. Belts and braces, perhaps, but I’m a completist and, more to the point, didn’t know how it was done and wanted to learn.
Tackle async signal safety in Swift
How do you safely interrupt a command-line program written in Swift? This question was posed to me this week by a reader who got in touch to point out that boilerplate code included in my How to write macOS command line tools in Swift post might not be totally safe: it could leave a program and system in an undefined state, which is never a good thing. So I took a closer look.

Stay ahead of git with this sharp script
I work on quite a few git repositories at once, and I don’t always commit changes in one before making changes to another. Or if I do, I don’t always push the changes up straight away. That might not be best practice in software development, but hey, it’s what I do. The issue for me is remembering what state each repo is in. Here’s the script I use to tell me.
Continue readingMNU now supports Mac terminal emulator iTerm2
MNU, my macOS menu bar utility that lets you call up regularly used command line operations and more, now supports iTerm2, the popular alternative to macOS’ own Terminal app.
Continue readingCrop picture files with confidence and pixel-precise offsets, using sips and imageprep
I recently had a rather large number of screenshots to process: specifically to crop them down to a small area about a third of screen width in and two-thirds of its height down. I could have done this manually, but it’s easy enough to make mis-crops when you’re cropping a couple of images by eye, let alone a 100 or so. The solution? Get your Mac to do it for you. Here’s how.
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