Well, this has been quiet for a while. Not because I stopped tinkering
— quite the opposite. Almost all of my time these days goes into Infix
OS, a Linux-based network operating system by Wires. The OS is
maintained under an independent organization, KernelKit, where I blog a
lot — so check out the KernelKit blog.
In my Reminder to Self series, this week we turn to some tricks I learned while porting U-Boot to a new board. First, a few tools:
vbindiff: Linux tool to examine, e.g., flash.bin binwalk: Linux tool to examine an unknown binary file bdinfo: U-Boot command to list board info When poking through such binaries, the FDT (flattened device tree) header magic to look for is 0xd00dfeed.
Huge props to wkz for all the help and sparring, cheers!
Here are a few Buildroot tricks I use to develop and test my packages. This post will likely evolve over the years to come.
For the basics, please see my post Buildroot Development Checklist. It covers how to use the check-package and test-pkg tools shipped with Buildroot.
Tip: if stuck, always check the Buildroot documentation!
introduction I often need to rebuild from scratch to verify fundamental changes to the structure of my embedded systems.
Very brief intro to building GNU Emacs from GIT, with GCC JIT enabled to greatly speed up our favorite editor, GNU Emacs!
Perquisites You need a lot of development packages installed to check out and build Emacs. How to install these are outside the scope of this blog post. The output of the configure script and some intuition is usually sufficient. On Debian, Ubuntu, or Linux Mint, systems at least the following is needed:
Daniel Lipovetsky’s Typometer results.
Ever since I first learned about Terminator I’ve been a huge fan! It’s a great replacement for the standard Gnome terminal with its built-in support for horizontal and vertical splits.
It’s not a race car though … like Gnome terminal it’s built around libvte. So on a bad day of clashing with Ubuntu, GDM, systemd and the new handling of capabilities, two of my colleagues went all-in on Alacritty and now swear by it!
Finit is an alternative to SysV init and systemd, originally reverse engineered from the EeePC fastinit by Claudio Matsuoka — “gaps filled with frog DNA …”
Latest release available on GitHub
Features Runlevels, defined per service One-shot tasks, services (daemons), or SysV init start/stop scripts Runparts and /etc/rc.local support Process supervision similar to systemd Sourcing environment files Conditions for network/process/custom dependencies Pre/Post script actions Tooling to enable/disable services Optional built-in getty Optional built-in watchdog, with support for hand-over to watchdogd Built-in support for Debian/BusyBox /etc/network/interfaces, automatically calls ifup/ifdown Cgroups v2, both configuration and monitoring in initctl top Plugin support for customization Proper rescue mode with bundled sulogin for protected maintenance shell (optional) Blog Posts Some of these feature are presented below, for more, see the online documentation and the following blog posts:
This mini HowTo describes how to use the SNMP client tools to retrieve human readable information from devices running an SNMP daemon. In the examples below mini-snmpd is used as the daemon and as client both the command line net-snmp tool and the snmpB GUI are used.
Personally I use both Ubuntu and Debian, so the tools I use to download the clients will reflect that. See your respective UNIX distro’s help pages for how to install these client tools in your operating system.
Introduction This HowTo attempts to give some insight into the basics of setting up multicast routing. Both static multicast routing, with SMCRoute, and dynamic multicast routing, with mrouted and pimd.
For some use-cases, in particular link-local multicast, it may not be possible to use multicast routing, then I recommend trying out:
Bridging networks, see bridge(8) or Linux bridge - how it works igmproxy, mcproxy, or OpenVPN in Layer-2, bridged mode Make sure to check out the FAQ for the most common problems.
