After so many months, I had no idea what tools I was running in that command line... And therefore, the effect of any signal seemed far more dangerous to me, than extracting the actual command from my shell's memory.
The answer to that is simpler: Try doing the Ctrl-z/fg sequence in your bash with this one:
while true ; do sleep 1 ; done
You'll see that after 'fg', the loop ends :-)
Simply put: C-z followed by fg is not bulletproof. Not to mention that I had no idea what I was running in there, and how any signal would impact it... So I wanted to find a safer way to dump what was already there, in my shell's memory.
Anyway, I hope you guys enjoyed reading this regardless :-)
The script was running in production, doing actual work. Stopping it - when you don't remember a damn thing about it and how it worked - was not an option I wanted to consider at the time.
Hi Rory. I am well aware of the flags you described - and indeed, they'd clean things up here. I am in fact tempted to go back and update the post - and either replace the shebang, or add the "early abort" flags.
But TBH, keeping that script (that I wrote in 60 seconds) nice and clean was the least of my worries... Making the damn toolchain work had far, far higher priority :-)
Yeah of course. I didn't mean to take anything away from the awesome work you are doing, this was nitpicking really, the script as it is, will work as intended, was really just highlighting this for the sake of others who may not be aware. Keep up the good work!
Actually, no - he meant the size in bytes. For example, my Digital Ocean droplet reports...
# egrep '^(cache |model )' /proc/cpuinfo
model name : Intel(R) Xeon(R) CPU E5-2630L 0 @ 2.00GHz
cache size : 15360 KB
To understand the context of the article's claim, let me just add that we used to make fun of Emacs people by saying the name stood for "Eight Megabytes And Constantly Swapping". That was a time when a machine with 8MB was a big one. You can see above that machines nowadays have caches larger than that!
And to compensate, we've now invented editors based on Javascript :-)
I started looking into this category of HW - SBCs, that is - 4 years ago. Initially, it was mostly curiosity ; to see whether I could apply my UNIX knowledge on these tiny machines, and whether I could coax them into doing actually useful things.
The result: I am addicted :-)
Not in the sense of idiotic consumerism - no, I only bought two of them (a Raspberry PI 2 and an Orange PI Zero). But in the sense of realizing that they can be put to many, many uses - and perform this work utilizing only a fraction of the energy cost of even the best of x86 designs.
I wrote a detailed blog post [1] about what I did with my 11 Euro (not a typo) Orange PI Zero. After that, I set it up as my NFS and Borgbackup server (i.e. I attached my two external portable USB drives on it - and it has multiple USB root-level hubs, so it gives me decent speed on them). A complete backup of my Arch Linux laptop (250GB SSD, MB Air from 2012) takes around 6 minutes to complete over Wi-Fi - and due to the magic of Borgbackup's deduplication, I have about 150 such complete "images" in a bit over 300GB total storage on the two drives. A periodic "scrub" run once a week makes sure there's no bit-rot - and if there is, the btrfs mirror over the two drives corrects it.
As for my Raspberry PI2...
- setup as an `sslh` gateway; this means that I can use `sshuttle` from the outside world to create on-the-spot SSH-based "VPN"s and access places that are blocked (during travels, work, etc). It basically "transports" my laptop/work computer into my home LAN.
- At the same time it is serving up my collected notes over the years on a Let's Encrypt-ed HTTPS private site via NGINX.
- FreeDNS provides a nice, easily accessible name for both these services.
- An attached RPI camera is used to take a picture every 5 seconds - and if the picture is sufficiently different from the previous one, it encrypts it and uploads it to my Digital Ocean droplet. Whatever happens to my apartment while I'm gone, I get a record of it on a remote server that only I can decode (the remote server doesn't have the GPG key necessary to do so, I have those on me).
- The SPI functionality of the PI is also used in my various micro-controller experiments - e.g. to "flash" my ATMEGA328p and have it do silly things [2].
- In general, I am tinkering with electronics - and there's a lot of fun in doing this with SBCs.
- At some point, I had it run exim4 as well; and got my mail-tester.com score up to 10/10.
The PI2 was 35Euros - the Orange PI zero 11 Euros.
The fun I've had building the stuff above? Learning skills? Connecting to them over serial ports and reliving my Uni-days?
# modprobe mei_me
# modprobe mei_txe
# modprobe mei
# lsmod | grep mei
mei_me 36864 0
mei_txe 20480 0
mei 86016 2 mei_me,mei_txe
# python2 ./intel_sa00086.py
INTEL-SA-00086 Detection Tool
Copyright(C) 2017, Intel Corporation, All rights reserved
Application Version: 1.0.0.128
Scan date: 2017-11-23 20:37:48 GMT
*** Host Computer Information ***
Name: mbair
Manufacturer: Apple Inc.
Model: MacBookAir5,2
Processor Name: Intel(R) Core(TM) i5-3427U CPU @ 1.80GHz
*** Intel(R) ME Information ***
Engine: Intel(R) Management Engine
Version: 8.0.4.1441
SVN: 0
*** Risk Assessment ***
Based on the analysis performed by this tool: This system is not vulnerable.
"This system is not vulnerable". Meh - one can never be sure with ME running silently in the background...
When the HW dies, I'll most probably go for a Chromebook with Coreboot - and install Debian on it.
I've had it - enough with this idiocy from Intel and AMD ; if they can't see how these "signed black boxes" are harming them, they deserve what's coming (open, and powerful enough architectures - i.MX8, RISC-V, etc).
After watching this video, I spent a few hours reproducing the core functionality of what Howard demonstrated (with an .org file of my own)...
...and then went further down the rabbit hole. I installed org-reveal and used it to create a very nice presentation out of my .org file - with syntax-highlighted code seemlessly merging with screenshots.
Incredible. Thanks for pointing me to this - and thank you, Howard!
