From 8c6e6d5b160140891b2f66de7483f00af54cffcc Mon Sep 17 00:00:00 2001 From: Neale Pickett Date: Sun, 8 Mar 2015 16:06:53 -0600 Subject: [PATCH] New paper on using runit --- papers/gui.mdwn | 63 ++++++++++++ papers/index.mdwn | 3 +- papers/runit-as-init.mdwn | 203 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 268 insertions(+), 1 deletion(-) create mode 100644 papers/gui.mdwn create mode 100644 papers/runit-as-init.mdwn diff --git a/papers/gui.mdwn b/papers/gui.mdwn new file mode 100644 index 0000000..d4524e5 --- /dev/null +++ b/papers/gui.mdwn @@ -0,0 +1,63 @@ +Title: Making Unix a little more Plan9-like + +I'm not really interested in defending anything. +I tried out plan9port and liked it, +but I have to live in Unix land. +Here's how I set that up. + +A Warning +-------- + +The suckless community, +and some of the plan9 communities, +are dominated by assholes. +I hope that's strong enough wording to impress the severity. +Don't go into IRC for help. +Stay off the suckless email list. +The software is great, +the people who write it are well-spoken and well-reasoned, +but for some reason the fandom is horrible to everyone. + +xterm +----- + +9term has some really cool ideas. +But Unix has a long history of using graphical terminals, +and lots of stuff needs VT220 compatibility. +xterm is a good compromise. + +You can make the xterm scroll bar (and all other Athena scrollbars) prettier +with this in your X resources: + + *Scrollbar.thickness: 10 + *Scrollbar.thumb: None + *Scrollbar.foreground: gray80 + *Scrollbar.background: gray50 + *Scrollbar.borderWidth: 3 + *ScrollBarBorder: 0 + +This will swap the left and right mouse buttons, +to work like acme and 9term: + + *Scrollbar.translations: #override\ + : StartScroll(Backward) \n\ + : StartScroll(Forward) \n\ + : NotifyScroll(Proportional) EndScroll() + +A side note: +if xrdb is never run and your root window doesn't have a +`RESOURCE_MANAGER` property set, +libXaw will read `$HOME/.Xdefaults`. +This is supposedly deprecated, +but Xaw is so ancient it will probably never be removed. + + +9wm +---- + +I'm now maintaining the 9wm window manager. +If you like rio you should give it a whirl, +there are some differences you might prefer. +http://woozle.org/neale/g.cgi/x11/9wm/ + + diff --git a/papers/index.mdwn b/papers/index.mdwn index a7b9e1a..900a04a 100644 --- a/papers/index.mdwn +++ b/papers/index.mdwn @@ -20,7 +20,8 @@ Computer Nerd Stuff * [The Setup](setup.html): the hardware and software I use * [Writing formal letters with roff](roff-letters.html) -* [Runit on Arch Linux](arch-runit.html) +* [Plan9 GUI stuff in Unix](gui.html): How to make your X11 stuff feel more like Plan9 +* [Runit as Init](arch-runit.html): My experience using runit as PID 1 for two years * [Reply-To Munging Still Considered Harmful](reply-to-still-harmful.html) * [Runnning PHP as a CGI](php-cgi.html) in anything other than Apache * [Converting .docx files to text using unzip and sed](docx.html) diff --git a/papers/runit-as-init.mdwn b/papers/runit-as-init.mdwn new file mode 100644 index 0000000..cf48200 --- /dev/null +++ b/papers/runit-as-init.mdwn @@ -0,0 +1,203 @@ +Title: My experiences using runit in Arch Linux + +In around 2012, +after using busybox runit instead of sysvinit in my +[Dirtbags Tiny Linux](https://woozle.org/neale/g.cgi/ctf/dbtl) +distribution, +I decided to try it out on my laptop, too. +Here's how that went. + +Older Stuff +=========== + +My older paper on specifics of the conversion +is still online: [Runit on Arch](arch-runit.html) + +Motivation +========== + +I wanted to see if I could get a working system without having systemd +installed at all. +Not because I hate systemd, +but because I love runit. +I am acutely aware that a lot of people have strong opinions about systemd. +Please: you don't need to share them with me. +I don't care. + +Replacing init +-------------- + +First and most obvious was to get a getty running with my own +`/sbin/init`. +At the time, +arch had just switched over to systemd, +and had a recently-maintained systemv-init. +Copying that, +I was able to write a new init in Bourne shell. +The resulting init did the following: + +* Mount and set up special filesystems (proc, sys, dev) +* Set the system clock +* Populate /dev (with `mdev -s`) +* Load drivers (by reading `modalias` files in /sys) +* Set the hostname +* Bring up the loopback network interface +* Set up cryptographic devices, if there are any +* `fsck -A` +* Remount / read-write +* Mount everything else +* Hand off to `runsvdir` + +Not bad, really. + + +Setting up runit services +------------------------- + +I won't go into this too much, it's well-documented elsewhere. +At this point, I was able to get a getty going, +but X11 wasn't recognizing the keyboard or mouse. + + +Making X11 work +--------------- + +X11 at the time wanted `udev`, +so I just ran that from init. +But, a few months later, +X was able to start with `udev`, +so I took it out and figured out the keyboard and mouse problem. + +It had something to do with `evdev`; +I think `udev` provided some sort of `evdev` help to X11, +so I had to create some files in `/etc/X11/xorg.conf.d` +to disable `AutoAddDevices`. +Then the keyboard and mouse worked. + +I never looked into how to get evdev working again. + + +Hot-plugging devices (like udev) +-------------------------------- + +For a while, +you could echo something into a file under `/proc` +and the kernel would run that for every uevent. +You could set that program to `mdev` from busybox, +and have a pretty well working system at that point. + +Newer kernels disabled support for this legacy interface. +Now, you're supposed to monitor for Netlink events. +But that's not too tough, it turns out. +The kernel docs even have an example program to gather uevents. + + +Wayland +------- + +All you had to do was make a group with a certain name and add yourself to it. +You also had to have write access to `/dev/dri/*` for the X11 stuff. +Wayland was actually pretty low on crazy requirements. +No consolekit or policykit or whatnottery needed. + + +That's all? +----------- + +Yup! + + +Retrospective View +================== + +After two years with this setup, +I'm back to Ubuntu now, +which means soon I'll have systemd. +Looking back on it, here's how it went. + + +It was blazing fast +------------------- + +My new Ubuntu install boots a lot slower than my runit thing did. +Maybe 2-3 times slower. +Of course, it's doing way more. +This is the cost of having a general-use distribution: +you have to account for lots of cases, +and need lots more support software. +You can't rely on the machine owner to debug when, +for instance, +the console user doesn't have write access to the DRI device. + + +It was easy (for me) +-------------------- + +Runit is really nice. +I like it a lot. +For old Unix beardos like me, +having everything in Bourne shell is an attractive proposition. + + + +It required high wizardry +------------------------- + +The head guy from the Archbang distribution tried to duplicate my work once, +and failed to make everything work. +We never did sort out what he needed to change. +This was not something I'd recommend trying if you're not an expert +and/or unwilling to debug a massively broken system for weeks. + + +Stuff that never quite worked +----------------------------- + +I had to set up a `dmix` device for ALSA, +which usually worked, +but sometimes things would get an exclusive lock on the sound hardware, +which prevented other things from making sound. + +I could never get Chrome to get sound from the USB webcam I had to use at work. +It would list it as a microphone source, +and occasionally if I kept selecting every mic source over and over, +it would start working. +But it was never consistent, +and I was never able to figure out why not. + +I never figured out how to get X11 to use evdev devices. + + +Parting thoughts +---------------- + +Systemd fixes a lot of really ugly hacks. +Things had become super kludgy, +and systemd cleans it all up. +I can't speak to systemd's architecture. +It was annoying at times when stuff seemed to depend on systemd, +but after looking into it, +I was always able to find another way to do it. + +Bear in mind, I never tried to run Gnome or KDE. +But I don't think people who want Gnome are going to want to futz around +with writing run scripts for lid button events. + +The Linux kernel does not, +to my mind, +appear to be making any huge changes for systemd. +Nothing I ran into here was out of reach for my project. + +Linux can still be used in a traditionally Unixy way. +But you have got to bear in mind how un-Unixy things like X11 are. +Wayland might be better, I don't know enough to say yet. + +My point is, Unix lost its roots decades ago with X11, +or maybe even before with the Berkeley socket API, +which didn't work from a shell script. +I think it would be cool if somebody tried to make Linux +look more like Plan9, +and maybe the current backlash will kick that off. +Runit is a way could do that. +Please feel free to contact me :) +