Search Results: "spa"

1 April 2020

Joachim Breitner: 30 years of Haskell

Vitaly Bragilevsky, in a mail to the GHC Steering Committee, reminded me that the first version of the Haskell programming language was released exactly 30 years ago. On April 1st. So that raises the question: Was Haskell just an April fool's joke that was never retracted?
The cover of the 1.0 Haskell report

The cover of the 1.0 Haskell report

My own first exposure to Haskell was in April 2005; the oldest piece of Haskell I could find on my machine is this part of a university assignment from April: 
> pascal 1 = [1]
> pascal (n+1) = zipWith (+) (x ++ [0]) (0 : x) where x = pascal n
This means that I now have witnessed half of Haskell's existence. I have never regretted getting into Haskell, and every time I come back from having worked in other languages (which all have their merits too), I greatly enjoy the beauty and elegance of expressing my ideas in a lazy and strictly typed language with a concise syntax. I am looking forward to witnessing (and, to a very small degree, shaping) the next 15 years of Haskell.

Sylvain Beucler: Debian LTS and ELTS - March 2020

Debian LTS Logo Here is my transparent report for my work on the Debian Long Term Support (LTS) and Debian Extended Long Term Support (ELTS), which extend the security support for past Debian releases, as a paid contributor. In March, the monthly sponsored hours were split evenly among contributors depending on their max availability - I was assigned 30h for LTS (out of 30 max; all done) and 20h for ELTS (out of 20 max; I did 0). Most contributors claimed vulnerabilities by performing early CVE monitoring/triaging on their own, making me question the relevance of the Front-Desk role. It could be due to a transient combination of higher hours volume and lower open vulnerabilities. Working as a collective of hourly paid freelancers makes it more likely to work in silos, resulting in little interaction when raising workflow topics on the mailing list. Maybe we're reaching a point where regular team meetings will be benefical. As previously mentioned, I structure my work keeping the global Debian security in mind. It can be stressful though, and I believe current communication practices may deter such initiatives. ELTS - Wheezy LTS - Jessie Documentation/Scripts

Joey Hess: DIN distractions

My offgrid house has an industrial automation panel. A row of electrical devices, mounted on a metal rail. Many wires neatly extend from it above and below, disappearing into wire gutters. I started building this in February, before covid-19 was impacting us here, when lots of mail orders were no big problem, and getting an unusual 3D-printed DIN rail bracket for a SSD was just a couple clicks. I finished a month later, deep into social isolation and quarentine, scrounging around the house for scrap wire, scavenging screws from unused stuff and cutting them to size, and hoping I would not end up in a "need just one more part that I can't get" situation. It got rather elaborate, and working on it was often a welcome distraction from the news when I couldn't concentrate on my usual work. I'm posting this now because people sometimes tell me they like hearing about my offfgrid stuff, and perhaps you could use a distraction too. The panel has my house's computer on it, as well as both AC and DC power distribution, breakers, and switching. Since the house is offgrid, the panel is designed to let every non-essential power drain be turned off, from my offgrid fridge to the 20 terabytes of offline storage to the inverter and satellite dish, the spring pump for my gravity flow water system, and even the power outlet by the kitchen sink. Saving power is part of why I'm using old-school relays and stuff and not IOT devices, the other reason is of course: IOT devices are horrible dystopian e-waste. I'm taking the utopian Star Trek approach, where I can command "full power to the vacuum cleaner!" Two circuit boards, connected by numerous ribbon cables, and clearly hand-soldered. The smaller board is suspended above the larger. An electrical schematic, of moderate complexity. At the core of the panel, next to the cubietruck arm board, is a custom IO daughterboard. Designed and built by hand to fit into a DIN mount case, it uses every GPIO pin on the cubietruck's main GPIO header. Making this board took 40+ hours, and was about half the project. It got pretty tight in there. This was my first foray into DIN rail mount, and it really is industrial lego -- a whole universe of parts that all fit together and are immensely flexible. Often priced more than seems reasonable for a little bit of plastic and metal, until you look at the spec sheets and the ratings. (Total cost for my panel was $400.) It's odd that it's not more used outside its niche -- I came of age in the Bay Area, surrounded by rack mount equipment, but no DIN mount equipment. Hacking the hardware in a rack is unusual, but DIN invites hacking. Admittedly, this is a second system kind of project, replacing some unsightly shelves full of gear and wires everywhere with something kind of overdone. But should be worth it in the long run as new gear gets clipped into place and it evolves for changing needs. Also, wire gutters, where have you been all my life? A cramped utility room with an entire wall covered with electronic gear, including the DIN rail, which is surrounded by wire gutters Detail of a wire gutter with the cover removed. Numerous large and small wires run along it and exit here and there. Finally, if you'd like to know what everything on the DIN rail is, from left to right: Ground block, 24v DC disconnect, fridge GFI, spare GFI, USB hub switch, computer switch, +24v block, -24v block, IO daughterboard, 1tb SSD, arm board, modem, 3 USB hubs, 5 relays, AC hot block, AC neutral block, DC-DC power converters, humidity sensor. Full width of DIN rail.

Paul Wise: FLOSS Activities March 2020

Changes

Issues

Review

Administration
  • Debian wiki: approve accounts

Communication

Sponsors The dh-make-perl feature requests, file bug report, File::Libmagic changes, autoconf-archive change, libpst work and the purple-discord upload were sponsored by my employer. All other work was done on a volunteer basis.

31 March 2020

Pau Garcia i Quiles: Uyuni 2020.03 released with enhanced Debian support!

Uyuni is a configuration and infrastructure management tool that saves you time and headaches when you have to manage and update tens, hundreds or even thousands of machines. Uyuni is a fork of Spacewalk that leverages Salt, Cobbler and containers to modernize it. Uyuni is the upstream for SUSE Manager (the main difference is support: with SUSE Manager you get it from SUSE; with Uyuni you get it from the community) and our development and feature discussion is done in the open. Last week we released Uyuni 2020.03, with much improved Debian support, coming from the community: we have got client tools (both the Salt stack and the traditional stack) for Debian 9 and 10, and bootstrapping support! In addition to that, Uyuni 2020.03 brings many other new features: While this version of Uyuni provides a much better experience for Debian sysadmins, we still have a lot of room for improvement: Do you want to help us with development, or just with feedback? Join our community on IRC, Gitter or the mailing lists. And check our user documentation, developer documentation and presentations. We are also participating in Google Summer of Code 2020. Hurry up and submit a proposal to provide Uyuni for Debian, and/or enhance Debian support!

Chris Lamb: Free software activities in March 2020

Here is my monthly update covering what I have been doing in the free software world during March 2020 (previous month): In addition, I did even more hacking on the Lintian static analysis tool for Debian packages, including:
Reproducible builds One of the original promises of open source software is that distributed peer review and transparency of process results in enhanced end-user security. However, whilst anyone may inspect the source code of free and open source software for malicious flaws, almost all software today is distributed as pre-compiled binaries. This allows nefarious third-parties to compromise systems by injecting malicious code into ostensibly secure software during the various compilation and distribution processes. The motivation behind the Reproducible Builds effort is to ensure no flaws have been introduced during this compilation process by promising identical results are always generated from a given source, thus allowing multiple third-parties to come to a consensus on whether a build was compromised. The initiative is proud to be a member project of the Software Freedom Conservancy, a not-for-profit 501(c)(3) charity focused on ethical technology and user freedom. Conservancy acts as a corporate umbrella allowing projects to operate as non-profit initiatives without managing their own corporate structure. If you like the work of the Conservancy or the Reproducible Builds project, please consider becoming an official supporter. This month, I: In our tooling, I also made the following changes to diffoscope, our in-depth and content-aware diff utility that can locate and diagnose reproducibility issues, including preparing and uploading version 138 to Debian: The Reproducible Builds project also operates a fully-featured and comprehensive Jenkins-based testing framework that powers tests.reproducible-builds.org. This month, I reworked the web-based package rescheduling tool to:
Debian LTS This month I have worked 18 hours on Debian Long Term Support (LTS) and 8 hours on its sister Extended LTS project. You can find out more about the Debian LTS project via the following video:
Debian Uploads For the Debian Privacy Maintainers team I requested that the pyptlib package be removed from the archive (#953429) as well as uploading onionbalance (0.1.8-6) to fix test failures under Pytest 3.x (#953535) and a new upstream release of nautilus-wipe. Finally, I sponsored an upload of bilibop (0.6.1) on behalf of Yann Amar.

Norbert Preining: Fixing the Breeze Dark theme for gtk3 apps

It has been now about two weeks that I switched to KDE/Plasma on all my desktops, and to my big surprise, that went much more smooth than I thought. There are only a few glitches with respect to the gtk3 part of the Breeze Dark theme I am using, which needed fixup.
Tab distinction As I wrote already in a previous blog, the active tab in all kinds of terminal emulators, but in fact everything that uses the gtk3 notebook widget, is not distinguishable from other tabs. It turned out that this fix is a bit convoluted, but still possible, see the linked blog. Just for completeness, here is the CSS code I use in ~/.config/gtk-3.0/gtk.css: 
notebook tab  
    /* background-color: #222; */
    padding: 0.4em;
    border: 0;
    border-color: #444;
    border-style: solid;
    border-width: 1px;
 
 
notebook tab:checked  
    /* background-color: #000; */
    background-image: none;
    border-color: #76C802;
 
 
notebook tab:checked label  
    color: #76C802;
    font-weight: 500;
 
 
notebook tab button  
    padding: 0;
    background-color: transparent;
    color: #ccc;
 
 
notebook tab button:hover  
  border: 0;
  background-image: none;
  border-color: #444;
  border-style: solid;
  border-width: 1px;
Scroll bars Another of the disturbing properties of the Breeze theme is the width-changing scroll bar. While not hovered upon, it is rather small, but when the mouse moves over it it expands its width. Now that might sound like a flashy cool idea, but in fact it is nothing but a PITA: When used with a terminal emulator, the result is that the line length changes when the mouse moves over the vertical scroll bar, and thus suddenly the layout (line break) changes for instant, which is really really disturbing. I can t imagine why developers ever come up with such a stupid idea. Anyway, the fix is not that difficult again, simply put the following into your ~/.config/gtk-3.0/gtk.css (adjusting the width to your liking) and all will be fine: 
.scrollbar.vertical slider, scrollbar.vertical slider  
        min-width: 10px;
Not that bad, right? Other than this I haven t found any disturbing issue with using the Breeze theme with gtk3 (and gtk2) apps! Hope that helps

30 March 2020

Axel Beckert: How do you type on a keyboard with only 46 or even 28 keys?

Some of you might have noticed that I m into keyboards since a few years ago into mechanical keyboards to be precise. Preface It basically started with the Swiss Mechanical Keyboard Meetup (whose website I started later on) was held in the hackerspace of the CCCZH. I mostly used TKL keyboards (i.e. keyboards with just the for me useless number block missing) and tried to get my hands on more keyboards with Trackpoints (but failed so far). At some point a year or two ago, I looking into smaller keyboards for having a mechanical keyboard with me when travelling. I first bought a Vortex Core at Candykeys. The size was nice and especially having all layers labelled on the keys was helpful, but nevertheless I soon noticed that the smaller the keyboards get, the more important is, that they re properly programmable. The Vortex Core is programmable, but not the keys in the bottom right corner which are exactly the keys I wanted to change to get a cursor block down there. (Later I found out that there are possibilities to get this done, either with an alternative firmware and a hack of it or desoldering all switches and mounting an alternative PCB called Atom47.) 40% Keyboards So at some point I ordered a MiniVan keyboard from The Van Keyboards (MiniVan keyboards will soon be available again at The Key Dot Company), here shown with GMK Paperwork (also bought from and designed by The Van Keyboards):
The MiniVan PCBs are fully programmable with the free and open source firmware QMK and started to use that more and more instead of bigger keyboards. Layers With the MiniVan I learned the concepts of layers. Layers are similar to what many laptop keyboards do with the Fn key and to some extent also what the German standard layout does with the AltGr key: Layers are basically alternative key maps you can switch with a special key (often called Fn , Fn1 , Fn2 , etc., or especially if there are two additional layers Raise and Lower ). There are several concepts how these layers can be reached with these keys: My MiniVan Layout For the MiniVan, two additional layers suffice easily, but since I have a few characters on multiple layers and also have mouse control and media keys crammed in there, I have three additional layers on my MiniVan keyboards:

TRNS means transparent, i.e. use the settings from lower layers.
I also use a feature that allows me to mind different actions to a key depending if I just tap the key or if I hold it. Some also call this tap dance . This is especially very popular on the usually rather huge spacebar. There, the term SpaceFn has been coined, probably after this discussion on Geekhack. I use this for all my layer switching keys: With this layout I can type English texts as fast as I can type them on a standard or TKL layout. German umlauts are a bit more difficult because it requires 4 to 6 key presses per umlaut as I use the Compose key functionality (mapped to the Menu key between the spacebars and the cursor block. So to type an on my MiniVan, I have to:
  1. press and release Menu (i.e. Compose); then
  2. press and hold either Shift-Spacebar (i.e. Shift-Fn1) or Slash (i.e. Fn2), then
  3. press N for a double quote (i.e. Shift-Fn1-N or Fn2-N) and then release all keys, and finally
  4. press and release the base character for the umlaut, in this case Shift-A.
And now just use these concepts and reduce the amount of keys to 28: 30% and Sub-30% Keyboards In late 2019 I stumbled upon a nice little keyboard kit shop on Etsy which I (and probably most other people in the mechanical keyboard scene) didn t take into account for looking for keyboards called WorldspawnsKeebs. They offer mostly kits for keyboards of 40% size and below, most of them rather simple and not expensive. For about 30 you get a complete sub-30% keyboard kit (without switches and keycaps though, but that very common for keyboard kits as it leaves the choice of switches and key caps to you) named Alpha28 consisting of a minimal Acrylic case and a PCB and electronics set. This Alpha28 keyboard is btw. fully open source as the source code, (i.e. design files) for the hardware are published under a free license (MIT license) on GitHub. And here s how my Alpha28 looks like with GMK Mitolet (part of the GMK Pulse group-buy) key caps:
So we only have character keys, Enter (labelled Data as there was no 1u Enter key with that row profile in that key cap set; I ll also call it Data for the rest of this posting) and a small spacebar, not even modifier keys. The Default Alpha28 Layout The original key layout by the developer of the Alpha28 used the spacbar as Shift on hold and as space if just tapped, and the Data key switches always to the next layer, i.e. it switches the layer permanently on tap and not just on hold. This way that key rotates through all layers. In all other layers, V switches back to the default layer. I assume that the modifiers on the second layer are also on tap and apply to the next other normal key. This has the advantage that you don t have to bend your fingers for some key combos, but you have to remember on which layer you are at the moment. (IIRC QMK allows you to show that via LEDs or similar.) Kinda just like vi. My Alpha28 Layout But maybe because I m more an Emacs person, I dislike remembering states myself and don t bind bending my fingers. So I decided to develop my own layout using tap-or-hold and only doing layer switches by holding down keys:

A triangle means that the settings from lower layers are used, N/A means the key does nothing.
It might not be very obvious, but on the default layer, all keys in the bottom row and most keys on the row ends have tap-or-hold configurations. Basic ideasBottom row if holdOther rows if holdHow the keys are divided into layersUsing the Alpha28 This layout works surprisingly well for me. Only for Minus, Equal, Single Quote and Semicolon I still often have to think or try if they re on Layer 1 or 2 as on my 40%s (MiniVan, Zlant, etc.) I have them all on layer 1 (and in general one layer less over all). And for really seldom used keys like Insert, PrintScreen, ScrollLock or Pause, I might have to consult my own documentation. They re somewhere in the middle of the keyboard, either on layer 1, 2, or 3. ;-) And of course, typing umlauts takes even two keys more per umlaut as on the MiniVan since on the one hand Menu is not on the default layer and on the other hand, I don t have this nice shifted number row and actually have to also press Shift to get a double quote. So to type an on my Alpha, I have to:
  1. press and release Space-F (i.e. Fn1-F) for Menu (i.e. Compose); then
  2. press and hold A-Spacebar-L (i.e. Shift-Fn1-L) for getting a double quote, then
  3. press and release the base character for the umlaut, in this case L-A for Shift-A (because we can t use A for Shift as I can t hold a key and then press it again :-).
Conclusion If the characters on upper layers are not labelled like on the Vortex Core, i.e. especially on all self-made layouts, typing is a bit like playing that old children s game Memory: as soon as you remember (or your muscle memory knows) where some special characters are, typing gets faster. Otherwise, you start with trial and error or look the documentation. Or give up. ;-) Nevertheless, typing on a sub-30% keyboard like the Alpha28 is much more difficult and slower than on a 40% keyboard like the MiniVan. So the Alpha28 very likely won t become my daily driver while the MiniVan defacto is my already my daily driver. But I like these kind of challenges as others like the game Memory . So I ordered three more 30% and sub-30% keyboard kits and WorldspawnsKeebs for soldering on the upcoming weekend during the COVID19 lockdown: And if I at some point want to try to type with even fewer keys, I ll try a Butterstick keyboard with just 20 keys. It s a chorded keyboard where you have to press multiple keys at the same time to get one charcter: So to get an A from the missing middle row, you have to press Q and Z simultaneously, to get Escape, press Q and W simultaneously, to get Control, press Q, W, Z and X simultaneously, etc. And if that s not even enough, I already bought a keyboard kit named Ginny (or Ginni, the developer can t seem to decide) with just 10 keys from an acquaintance. Couldn t resist when offered his surplus kits. :-) It uses the ASETNIOP layout which was initially developed for on-screen keyboards on tablets.

Louis-Philippe V ronneau: Using Zoom's web client on Linux

TL;DR: The zoom meeting link you have probably look like this: 
https://zoom.us/j/123456789
To use the web client, use this instead: 
https://zoom.us/wc/join/123456789
Avant-propos Like too many institutions, the school where I teach chose to partner up with Zoom. I wasn't expecting anything else, as my school's IT department is a Windows shop. Well, I guess I'm still a little disappointed. Although I had vaguely heard of Zoom before, I had never thought I'd be forced to use it. Lucky for me, my employer decided not to force us to use it. To finish the semester, I plan to record myself and talk with my students on a Jitsi Meet instance. I will still have to attend meetings on Zoom though. I'm well aware of Zoom's bad privacy record and I will not install their desktop application. Zoom does offer a web client. Sadly, on Linux you need to jump through hoops to be able to use it. Using Zoom's web client on Linux Zoom's web client apparently works better on Chrome, so I decided to use Chromium. Without already having the desktop client installed on your machine, the standard procedure to use the web client would be:
  1. Open the link to the meeting in Chromium
  2. Click on the "download & run Zoom" link showed on the page
  3. Click on the "join from your browser" link that then shows up
Sadly, that's not what happens on Linux. When you click on the "download & run Zoom" link, it brings you to a page with instructions on how to install the desktop client on Linux. You can thwart that stupid behavior by changing your browser's user agent to make it look like you are using Windows. This is the UA string I've been using: 
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.149 Safari/537.36
With that, when you click on the "download & run Zoom" link, it will try to download a .exe file. Cancel the download and you should now see the infamous "join from your browser" link. Upon closer inspection, it seem you can get to the web client by changing the meeting's URL. The zoom meeting link you have probably look like this: 
https://zoom.us/j/123456789
To use the web client, use this instead: 
https://zoom.us/wc/join/123456789
Jitsi Meet Puppet Module I've been playing around with Jitsi Meet quite a bit recently and I've written a Puppet module to install and configure an instance! The module certainly isn't perfect, but should wield a working Jitsi instance. If you already have a Puppet setup, please give it a go! I'm looking forward receiving feedback (and patches) to improve it.

Shirish Agarwal: Covid 19 and the Indian response.

There have been lot of stories about Coronavirus and with it a lot of political blame-game has been happening. The first step that India took of a lockdown is and was a good step but without having a plan as to how especially the poor and the needy and especially the huge migrant population that India has (internal migration) be affected by it. A 2019 World Economic Forum shares the stats. as 139 million people. That is a huge amount of people and there are a variety of both push and pull factors which has displaced these huge number of people. While there have been attempts in the past and probably will continue in future they will be hampered unless we have trust-worthy data which is where there is lots that need to be done. In the recent few years, both the primary and secondary data has generated lot of controversies within India as well as abroad so no point in rehashing all of that. Even the definition of who is a migrant needs to be well-established just as who is a farmer . The simplest lucanae in the later is those who have land are known as farmers but the tenant farmers and their wives are not added as farmers hence the true numbers are never known. Is this an India-specific problem or similar definition issues are there in the rest of the world I don t know.

How our Policies fail to reach the poor and the vulnerable The sad part is most policies in India are made in castles in the air . An interview by the wire shares the conundrum of those who are affected and the policies which are enacted for them (it s a youtube video, sorry)
If one with an open and fresh mind sees the interview it is clear that why there was a huge reverse migration from Indian cities to villages. The poor and marginalized has always seen the Indian state as an extortive force so it doesn t make sense for them to be in the cities. The Prime Minister s annoucement of food for 3 months was a clear indication for the migrant population that for 3 months they will have no work. Faced with such a scenario, the best option for them was to return to their native places. While videos of huge number of migrants were shown of Delhi, this was the scenario of most states and cities, including Pune, my own city . Another interesting point which was made is most of the policies will need the migrants to be back in the villages. Most of these are tied to the accounts which are opened in villages, so even if they want to have the benefits they will have to migrate to villages in order to use them. Of course, everybody in India knows how leaky the administration is. The late Shri Rajiv Gandhi had famously and infamously remarked once how leaky the Public Distribution system and such systems are. It s only 10 paise out of rupee which reaches the poor. And he said this about 30 years ago. There have been numerous reports of both IPS (Indian Police Services) reforms and IAS (Indian Administrative Services) reforms over the years, many of the committee reports have been in public domain and in fact was part of the election manifesto of the ruling party in 2014 but no movement has happened on that part. The only thing which has happened is people from the ruling party have been appointed on various posts which is same as earlier governments. I was discussing with a friend who is a contractor and builder about the construction labour issues which were pointed in the report and if it is true that many a times the migrant labour is not counted. While he shared a number of cases where he knew, a more recent case in public memory was when some labourers died while building Amanora mall which is perhaps one of largest malls in India. There were few accidents while constructing the mall. Apparently, the insurance money which should have gone to the migrant laborer was taken by somebody close to the developers who were building the mall. I have a friend in who lives in Jharkhand who is a labour officer. She has shared with me so many stories of how the labourers are exploited. Keep in mind she has been a labor officer appointed by the state and her salary is paid by the state. So she always has to maintain a balance of ensuring worker s rights and the interests of the state, private entities etc. which are usually in cahoots with the state and it is possible that lot of times the State wins over the worker s rights. Again, as a labour officer, she doesn t have that much power and when she was new to the work, she was often frustrated but as she remarked few months back, she has started taking it easy (routinized) as anyways it wasn t helping her in any good way. Also there have been plenty of cases of labor officers being murdered so its easier to understand why one tries to retain some sanity while doing their job.

The Indian response and the World Response The Indian response has been the lockdown and very limited testing. We seem to be following the pattern of UK and U.S. which had been slow to respond and slow to testing. In the past Kerala showed the way but this time even that is not enough. At the end of the day we need to test, test and test just as shared by the WHO chairman. India is trying to create its own cheap test kits with ICMR approval, for e.g. a firm from my own city Pune MyLab has been given approval. We will know how good or bad they are only after they have been field-tested. For ventilators we have asked Mahindra and Mahindra even though there are companies like Allied Medical and others who have exported to EU and others which the Govt. is still taking time to think through. This is similar to how in UK some companies who are with the Govt. but who have no experience in making ventilators are been given orders while those who have experience and were exporting to Germany and other countries are not been given orders. The playbook is errily similar. In India, we don t have the infrastructure for any new patients, period. Heck only a couple of states have done something proper for the anganwadi workers. In fact, last year there were massive strikes by anganwadi workers all over India but only NDTV showed a bit of it along with some of the news channels from South India. Most mainstream channels chose to ignore it. On the world stage, some of the other countries and how they have responded perhaps need sharing. For e.g. I didn t know that Cuba had so many doctors and the politics between it and Brazil. Or the interesting stats. shared by Andreas Backhaus which seems to show how distributed the issue (age-wise) is rather than just a few groups as has been told in Indian media. What was surprising for me is the 20-29 age group which has not been shared so much in the Indian media which is the bulk of our population. The HBR article also makes a few key points which I hope both the general public and policymakers both in India as well as elsewhere take note of. What is worrying though that people can be infected twice or more as seems to be from Singapore or China and elsewhere. I have read enough of Robin Cook and Michael Crichton books to be aware that viruses can do whatever. They will over time mutate, how things will happen then is anybody s guess. What I found interesting is the world economic forum article which hypothesis that it may be two viruses which got together as well as research paper from journal from poteome research which has recently been published. The biggest myth flying around is that summer will halt or kill the spread which even some of my friends have been victim of . While a part of me wants to believe them, a simple scientific fact has been viruses have probably been around us and evolved over time, just like we have. In fact, there have been cases of people dying due to common cold and other things. Viruses are so prevalent it s unbelivable. What is and was interesting to note is that bat-borne viruses as well as pangolin viruses had been theorized and shared by Chinese researchers going all the way back to 90 s . The problem is even if we killed all the bats in the world, some other virus will take its place for sure. One of the ideas I had, dunno if it s feasible or not that at least in places like Airports, we should have some sort of screenings and a labs working on virology. Of course, this will mean more expenses for flying passengers but for public health and safety maybe it would worth doing so. In any case, virologists should have a field day cataloging various viruses and would make it harder for viruses to spread as fast as this one has. The virus spread also showed a lack of leadership in most of our leaders who didn t react fast enough. While one hopes people do learn from this, I am afraid the whole thing is far from over. These are unprecedented times and hope that all are maintaining social distancing and going out only when needed.

29 March 2020

Enrico Zini: Politics links

How tech's richest plan to save themselves after the apocalypse
politics privilege archive.org
2020-03-30
Silicon Valley s elite are hatching plans to escape disaster and when it comes, they ll leave the rest of us behind
Life of Privilege Explained in a $100 Race
privilege
2020-03-30
Hierarchy problems in autiautoritarian groups, and how to face them
chart politics archive.org
2020-03-30
Abstruse Goose The Story of the Cheese Maze
comics politics privilege archive.org
2020-03-30
Heteronomy - Wikipedia
language politics archive.org
2020-03-30
Heteronomy refers to action that is influenced by a force outside the individual, in other words the state or condition of being ruled, governed, or under the sway of another, as in a military occupation.
Poster - Early Warning Signs of Fascism
fascism politics archive.org
2020-03-30
Poster P590CW $9.00 Early Warning Signs Of Fascism Laurence W. Britt wrote about the common signs of fascism in April, 2003, after researching seven fascist regimes: Hitler's Nazi Germany; Mussolini's Italy; Franco's Spain; Salazar's Portugal; Papadopoulos' Greece; Pinochet's Chile; Suharto's Indonesia. Get involved! Text: Early Warning Signs of Fascism Powerful and Continuing Nationalism Disdain For Human Rights Identification of Enemies As a unifying cause Supremacy of the military Rampant Sexism Controlled Mass Media Obsession With National Security
Mobilizing in Times of Social Media
politics archive.org
2020-03-30
Political and social scientist Stefania Milan writes about social movements, mobilization and organized collective action. On the one hand, interactions and networks achieve more visibility and become a proxy for a collective we . On the other hand: Law enforcement can exercise preemptive monitorin
The Billion-Dollar Disinformation Campaign to Reelect the President
perception politics archive.org
2020-03-30
How new technologies and techniques pioneered by dictators will shape the 2020 election
An Italian Flash Mob Just Pushed Back Europe s Populist Tide
perception politics archive.org
2020-03-30
A regional election offers lessons on combatting the rise of the far right, both across the Continent and in the United States.
Italian diaspora - Wikipedia
italy politics archive.org
2020-03-30
The Italian diaspora is the large-scale emigration of Italians from Italy. There are two major Italian diasporas in Italian history. The first diaspora began more or less around 1880, a decade or so after the Unification of Italy (with most leaving after 1880), and ended in the 1920s to early-1940s with the rise of Fascism in Italy. The second diaspora started after the end of World War II and roughly concluded in the 1970s. These together constituted the largest voluntary emigration period in documented history. Between 1880-1980, about 15,000,000 Italians left the country permanently. By 1980, it was estimated that about 25,000,000 Italians were residing outside Italy. A third wave is being reported in present times, due to the socio-economic problems caused by the financial crisis of the early twenty-first century, especially amongst the youth. According to the Public Register of Italian Residents Abroad (AIRE), figures of Italians abroad rose from 3,106,251 in 2006 to 4,636,647 in 2015, growing by 49.3% in just ten years.

Paulo Henrique de Lima Santana: My free software activities in February 2020

My free software activities in february 2020 March is ending but I finally wrote my monthly report about activities in Debian and Free Software in general for February. As I already wrote here, I attended to FOSDEM 2020 on February 1st and 2nd in Brussels. It was a amazing experience. After my return to Curitiba, I felt my energies renewed to start new challenges.

MiniDebConf Macei 2020 I continued helping to organize MiniDebConf and I got positive answers from 4Linux and Globo.com and they are sponsorsing the event.

FLISOL 2020 I started to talk with Maristela from IEP - Instituto de Engenharia do Paran and after some messages and I joined a meeting with her and other members of C mara T cnica de Eletr nica, Computa o e Ci ncias de Dados. I explained about FLISOL in Curitiba to them and they agreed to host the event at IEP. I asked to use three spaces: Auditorium for FLISOL talks, Sal o Nobre for meetups from WordPress and PostgreSQL Communities, and the hall for Install Fest. Besides FLISOL, they would like to host other events and meetups from Communities in Curitiba as Python, PHP, and so on. At least one per month. I helped to schedule a PHP Paran Community meetup on March.

New job Since 17th I started to work at Rentcars as Infrastructure Analyst. I m very happy to work there because we use a lot of FLOSS and with nice people. Ubuntu LTS is the approved OS for desktops but I could install Debian on my laptop :-)

Misc I signed pgp keys from friends I met in Brussels and I had my pgp key signed by them. Finally my MR to the DebConf20 website fixing some texts was accepted. I have watched v deos from FOSDEM
  1. Until now, I saw these great talks:
  • Growing Sustainable Contributions Through Ambassador Networks
  • Building Ethical Software Under Capitalism
  • Cognitive biases, blindspots and inclusion
  • Building a thriving community in company-led open source projects
  • Building Community for your Company s OSS Projects
  • The Ethics of Open Source
  • Be The Leader You Need in Open Source
  • The next generation of contributors is not on IRC
  • Open Source Won, but Software Freedom Hasn t Yet
  • Open Source Under Attack
  • Lessons Learned from Cultivating Open Source Projects and Communities
That s all folks!

26 March 2020

Axel Beckert: Pictures in pure HTML with chafa and aha

I recently stumbled upon chafa, a tool to display pictures, especially color pictures on your ANSI text terminal, e.g. inside an xterm. And I occasionally use aha, the Ansi HTML Adapter to convert a colorful terminal content into HTML to show off terminal screenshots without the requirement of a picture so that it also works in e.g. text browsers or for blinds. Combining chafa and aha: Examples A moment ago I had the thought what would happen if I feed the output of chafa into aha and expected nothing really usable. But I was surprised by the quality of the outcome.
looks like this after chafa -w 9 -c full -s 160x50 DSCN4692.jpg aha -n:
Checking the Look in Text Browsers It even looks not that bad in elinks as far as I know the only text browser which supports CSS and styles:
In Lynx and Links 2, the text composing the image is displayed only in black and white, but you at least can recognise the edges in the picture:
Same Functionality in One Tool? I knew there was a tool which did this in one step. Seems to have been png2html. Tried to play around with it, too, but neither really understood how to use it (seems to require a text file for the characters to be used why?) nor did I really got it working. It always ran until I aborted it and it never filled the target file with any content. Additionally, png2html insists on one character per pixel, requiring to first properly resize the image before converting to HTML. The Keyboard in the Pictures Oh, and btw., the displayed keyboard is my Zlant. The Zlant is a 40% uniform staggered mechanical keyboard. Currently, only Zlant PCBs are available at 1UP Keyboards (USA), i.e. no complete kits. It is shown with the SA Vilebloom key cap set, currently available at MechSupply (UK).

25 March 2020

Raphaël Hertzog: Freexian s report about Debian Long Term Support, February 2020

A Debian LTS logo Like each month, here comes a report about the work of paid contributors to Debian LTS. Individual reports In February, 226 work hours have been dispatched among 14 paid contributors. Their reports are available: Evolution of the situation February began as rather calm month and the fact that more contributors have given back unused hours is an indicator of this calmness and also an indicator that contributing to LTS has become more of a routine now, which is good. In the second half of February Holger Levsen (from LTS) and Salvatore Bonaccorso (from the Debian Security Team) met at SnowCamp in Italy and discussed tensions and possible improvements from and for Debian LTS. The security tracker currently lists 25 packages with a known CVE and the dla-needed.txt file has 21 packages needing an update. Thanks to our sponsors New sponsors are in bold.

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24 March 2020

Dirk Eddelbuettel: New package RcppDate 0.0.1 now on CRAN!

A new small package with a new C++ header library is now on CRAN. It brings the date library by Howard Hinnant to R. This library has been in pretty wide-spread use for a while now, and adds to C++11/C++14/C++17 what will be (with minor modifications) the date library in C++20. I had been aware of it for a while, but not needed thanks to CCTZ library out of Google and our RcppCCTZ package. And like CCTZ, it builds upon std::chron adding a whole lot of functionality and useability enhancement. But a some upcoming (and quite exciting!) changes in nanotime required it, I had a reason to set about packaging it as RcppDate. And after a few days of gestation and review it is now available via CRAN. Two simple example files are included and can be accessed by Rcpp::sourceCpp(). Some brief excerpts follow. The first example shows three date constructors. Note how the month (and the leading digits) are literals. No quotes for strings anywhere. And no format (just like our anytime package for R). 
  constexpr auto x1 = 2015_y/March/22;
  constexpr auto x2 = March/22/2015;
  constexpr auto x3 = 22_d/March/2015;
Note that these are constexpr that resolve at compile-time, and that the resulting year_month_day type is inferred via auto. A second example constructs the last day of the months similarly: 
  constexpr auto x1 = 2015_y/February/last;
  constexpr auto x2 = February/last/2015;
  constexpr auto x3 = last/February/2015;
For more, see the copious date.h documentation. The (very bland first) NEWS entry (from a since-added NEWS file) for the initial upload follows.

Changes in version 0.0.1 (2020-01-17)
  • Initial CRAN upload of first version

If you like this or other open-source work I do, you can now sponsor me at GitHub. For the first year, GitHub will match your contributions.

This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. Please report excessive re-aggregation in third-party for-profit settings.

Christoph Berg: Announcing apt-archive.postgresql.org

Users had often asked where they could find older versions of packages from apt.postgresql.org. I had been collecting these since about April 2013, and in July 2016, I made the packages available via an ad-hoc URL on the repository master host, called "the morgue". There was little repository structure, all files belonging to a source package were stuffed into a single directory, no matter what distribution they belonged to. Besides this not being particularly accessible for users, the main problem was the ever-increasing need for more disk space on the repository host. We are now at 175 GB for the archive, of which 152 GB is for the morgue. Our friends from yum.postgresql.org have had a proper archive host (yum-archive.postgresql.org) for some time already, so it was about time to follow suit and implement a proper archive for apt.postgresql.org as well, usable from apt. So here it is: apt-archive.postgresql.org The archive covers all past and current Debian and Ubuntu distributions. The apt sources.lists entries are similar to the main repository, just with "-archive" appended to the host name and the distribution: 
deb https://apt-archive.postgresql.org/pub/repos/apt DIST-pgdg-archive main
deb-src https://apt-archive.postgresql.org/pub/repos/apt DIST-pgdg-archive main
The oldest PostgreSQL server versions covered there are 8.2.23, 8.3.23, 8.4.17, 9.0.13, 9.1.9, 9.2.4, 9.3beta1, and everything newer. Some example: 
$ apt-cache policy postgresql-12
postgresql-12:
  Installed: 12.2-2.pgdg+1+b1
  Candidate: 12.2-2.pgdg+1+b1
  Version table:
 *** 12.2-2.pgdg+1+b1 900
        500 http://apt.postgresql.org/pub/repos/apt sid-pgdg/main amd64 Packages
        500 https://apt-archive.postgresql.org/pub/repos/apt sid-pgdg-archive/main amd64 Packages
        100 /var/lib/dpkg/status
     12.2-2.pgdg+1 500
        500 https://apt-archive.postgresql.org/pub/repos/apt sid-pgdg-archive/main amd64 Packages
     12.2-1.pgdg+1 500
        500 https://apt-archive.postgresql.org/pub/repos/apt sid-pgdg-archive/main amd64 Packages
     12.1-2.pgdg+1 500
        500 https://apt-archive.postgresql.org/pub/repos/apt sid-pgdg-archive/main amd64 Packages
     12.1-1.pgdg+1 500
        500 https://apt-archive.postgresql.org/pub/repos/apt sid-pgdg-archive/main amd64 Packages
     12.0-2.pgdg+1 500
        500 https://apt-archive.postgresql.org/pub/repos/apt sid-pgdg-archive/main amd64 Packages
     12.0-1.pgdg+1 500
        500 https://apt-archive.postgresql.org/pub/repos/apt sid-pgdg-archive/main amd64 Packages
     12~rc1-1.pgdg+1 500
        500 https://apt-archive.postgresql.org/pub/repos/apt sid-pgdg-archive/main amd64 Packages
     12~beta4-1.pgdg+1 500
        500 https://apt-archive.postgresql.org/pub/repos/apt sid-pgdg-archive/main amd64 Packages
     12~beta3-1.pgdg+1 500
        500 https://apt-archive.postgresql.org/pub/repos/apt sid-pgdg-archive/main amd64 Packages
     12~beta2-1.pgdg+1 500
        500 https://apt-archive.postgresql.org/pub/repos/apt sid-pgdg-archive/main amd64 Packages
     12~beta1-1.pgdg+1 500
        500 https://apt-archive.postgresql.org/pub/repos/apt sid-pgdg-archive/main amd64 Packages
Because this is hosted on S3, browsing directories is only supported indirectly by static index.html files, so if you want to look at some specific URL, append "/index.html" to see it. The archive is powered by a PostgreSQL database and a bunch of python/shell scripts, from which the apt index files are built. Archiving old distributions I'm also using the opportunity to remove some long-retired distributions from the main repository host. The following distributions have been moved over: They are available as "DIST-pgdg" from the archive, e.g. squeeze: 
deb https://apt-archive.postgresql.org/pub/repos/apt squeeze-pgdg main
deb-src https://apt-archive.postgresql.org/pub/repos/apt squeeze-pgdg main

Russ Allbery: Review: Lost in Math

Review: Lost in Math, by Sabine Hossenfelder
Publisher: Basic
Copyright: June 2018
ISBN: 0-465-09426-0
Format: Kindle
Pages: 248
Listening to experts argue can be one of the better ways to learn about a new field. It does require some basic orientation and grounding or can be confusing or, worse, wildly misleading, so some advance research or Internet searches are warranted. But it provides some interesting advantages over reading multiple popular introductions to a field. First, experts arguing with each other are more precise about their points of agreement and disagreement because they're trying to persuade someone who is well-informed. The points of agreement are often more informative than the points of disagreement, since they can provide a feel for what is uncontroversial among experts in the field. Second, internal arguments tend to be less starry-eyed. One of the purposes of popularizations of a field is to get the reader excited about it, and that can be fun to read. But to generate that excitement, the author has a tendency to smooth over disagreements and play up exciting but unproven ideas. Expert disagreements pull the cover off of the uncertainty and highlight the boundaries of what we know and how we know it. Lost in Math (subtitled How Beauty Leads Physics Astray) is not quite an argument between experts. That's hard to find in book form; most of the arguments in the scientific world happen in academic papers, and I rarely have the energy or attention span to read those. But it comes close. Hossenfelder is questioning the foundations of modern particle physics for the general public, but also for her fellow scientists. High-energy particle physics is facing a tricky challenge. We have a solid theory (the standard model) which explains nearly everything that we have currently observed. The remaining gaps are primarily at very large scales (dark matter and dark energy) or near phenomena that are extremely difficult to study (black holes). For everything else, the standard model predicts our subatomic world to an exceptionally high degree of accuracy. But physicists don't like the theory. The details of why are much of the topic of this book, but the short version is that the theory does not seem either elegant or beautiful. It relies on a large number of measured constants that seem to have no underlying explanation, which is contrary to a core aesthetic principle that physicists use to judge new theories. Accompanying this problem is another: New experiments in particle physics that may be able to confirm or disprove alternate theories that go beyond the standard model are exceptionally expensive. All of the easy experiments have been done. Building equipment that can probe beyond the standard model is incredibly expensive, and thus only a few of those experiments have been done. This leads to two issues: Particle physics has an overgrowth of theories (such as string theory) that are largely untethered from experiments and are not being tested and validated or disproved, and spending on new experiments is guided primarily by a sense of scientific aesthetics that may simply be incorrect. Enter Lost in Math. Hossenfelder's book picks up a thread of skepticism about string theory (and, in Hossenfelder's case, supersymmetry as well) that I previously read in Lee Smolin's The Trouble with Physics. But while Smolin's critique was primarily within the standard aesthetic and epistemological framework of particle physics, Hossenfelder is questioning that framework directly. Why should nature be beautiful? Why should constants be small? What if the universe does have a large number of free constants? And is the dislike of an extremely reliable theory on aesthetic grounds a good basis for guiding which experiments we fund?
Do you recall the temple of science, in which the foundations of physics are the bottommost level, and we try to break through to deeper understanding? As I've come to the end of my travels, I worry that the cracks we're seeing in the floor aren't really cracks at all but merely intricate patterns. We're digging in the wrong places.
Lost in Math will teach you a bit less about physics than Smolin's book, although there is some of that here. Smolin's book was about two-thirds physics and one-third sociology of science. Lost in Math is about two-thirds sociology and one-third physics. But that sociology is engrossing. It's obvious in retrospect, but I hadn't thought before about the practical effects of running out of unexplained data on a theoretical field, or about the transition from more data than we can explain to having to spend billions of dollars to acquire new data. And Hossenfelder takes direct aim at the human tendency to find aesthetically appealing patterns and unified explanations, and scores some palpable hits.
I went into physics because I don't understand human behavior. I went into physics because math tells it how it is. I liked the cleanliness, the unambiguous machinery, the command math has over nature. Two decades later, what prevents me from understanding physics is that I still don't understand human behavior. "We cannot give exact mathematical rules that define if a theory is attractive or not," says Gian Francesco Giudice. "However, it is surprising how the beauty and elegance of a theory are universally recognized by people from different cultures. When I tell you, 'Look, I have a new paper and my theory is beautiful,' I don't have to tell you the details of my theory; you will get why I'm excited. Right?" I don't get it. That's why I am talking to him. Why should the laws of nature care what I find beautiful? Such a connection between me and the universe seems very mystical, very romantic, very not me. But then Gian doesn't think that nature cares what I find beautiful, but what he finds beautiful.
The structure of this book is half tour of how physics judges which theories are worthy of investigation and half personal quest to decide whether physics has lost contact with reality. Hossenfelder approaches this second thread with multiple interviews of famous scientists in the field. She probes at their bases for preferring one theory over another, at how objective those preferences can or should be, and what it means for physics if they're wrong (as increasingly appears to be the case for supersymmetry). In so doing, she humanizes theory development in a way that I found fascinating. The drawback to reading about ongoing arguments is the lack of a conclusion. Lost in Math, unsurprisingly, does not provide an epiphany about the future direction of high-energy particle physics. Its conclusion, to the extent that it has one, is a plea to find a way to put particle physics back on firmer experimental footing and to avoid cognitive biases in theory development. Given the cost of experiments and the nature of humans, this is challenging. But I enjoyed reading this questioning, contrarian take, and I think it's valuable for understanding the limits, biases, and distortions at the edge of new theory development. Rating: 7 out of 10

23 March 2020

Norbert Preining: De-uglify GTk3 tabs of terminals

If you are puzzled by the indistinguishability of the active tab from inactive tabs in any of the GTK3 based terminal emulators (mate-terminal, gnome-terminal, terminator, ), you are not alone. I have been plagued by that for far too long, and finally found a working solution.
In the above screen shot you see the tabs in the upper part are hardly distinguishable, and in the lower part the active tab is clearly indicated with different colors. Searching for relevant search terms brings up a variety of suggestions, most of them not working. I finally found this one and adapted the code therein to fit my need. The solution is to edit ~/.config/gtk-3.0/gtk.css, and add the following at the end: 
notebook tab  
    /* background-color: #222; */
    padding: 0.4em;
    border: 0;
    border-color: #444;
    border-style: solid;
    border-width: 1px;
 
 
notebook tab:checked  
    /* background-color: #000; */
    background-image: none;
    border-color: #76C802;
 
 
notebook tab:checked label  
    color: #76C802;
    font-weight: 500;
 
 
notebook tab button  
    padding: 0;
    background-color: transparent;
    color: #ccc;
 
 
notebook tab button:hover  
  border: 0;
  background-image: none;
  border-color: #444;
  border-style: solid;
  border-width: 1px;
Here I didn t change the background color (commented above), but changed the styling of the tab title and added a frame. The above changes the tab layout for all GTk3 elements that use the notebook widget, if one wants to restrict it to a certain terminal one need to prefix each CSS selector with the correct terminal indicator, as shown in the original post. Hope that helps.

Emmanuel Kasper: Two Factor Authentification on gitlab with Yubikey

I wanted to have a working Two Factor Authentification (2FA) setup to login on salsa.debian.org, Debians s gitlab instance.
You might already know Two Factor Authentification via a One Time Password (OTP) generating app on your smartphone, like FreeOTP or Google Authenticator. But it is possible to use a physical device, and a keypress on the device is enough to authenticate (speed up things !). Here I am using a Yubikey 4, a popular USB device for Two Factor Authentification which is officially supported by gitlab, and whose tooling is well packaged in Debian.
Get to know the deviceInstall the needed packages to work with the yubikey
# apt install yubikey-manager libu2f-host0
List connected devices on your usb bus:
$ lsusb
Bus 002 Device 109: ID 1050:0407 Yubico.com Yubikey 4 OTP+U2F+CCID
Get info about the device capability
$ ykman info
Device type: YubiKey 4
Serial number: 1234567
Firmware version: 4.3.7
Enabled USB interfaces: OTP+FIDO+CCID
Applications
OTP         Enabled             
FIDO U2F    Enabled             
OpenPGP     Enabled             
PIV         Enabled             
OATH            Enabled             
FIDO2       Not available
The capability which interests us here is FIDO U2F. The Yubikey 4 supports Two Factor Authentification via the U2F standard, and this standard is maintained by the FIDO Industry Association, hence the name. As I plan to only use the FIDO U2F capability of the key, I set FIDO to be the single mode of the key.
ykman mode FIDO
Testing web browser interaction with Yubico demo systemNow we need to have to have a browser with support for the U2F standard. Firefox has builtin support since Version 67. Debian 10 Buster has firefox-esr Version 68, so that will work. For testing yubikeys, the manufacturer has a demo website, where you can test U2F. Go to https://demo.yubico.com and follow the Explore the Yubikey link.
Once there you will be asked to register an account on yubicom s demo systems, to which you will add the Yubikey as an Authenticating Device. After that you can add your security key. First step will be to register the device, which will require a light touch on the Yubikey button, and acceptance of this Firefox warning Window, as the demo website wants to know the model of the device.


Firefox message on the yubikey demo site. A normal site with U2F would not require the extended information, and have a simpler popup message.
As soon as the device is registered, you can login and logout and you will be prompted again to lightly touch the Yubikey button to authenticate, in addition to the classical login / password.
Using U2F on gitlabWhen you want to register your yubikey for logging on salsa, you need first to register a One Time Password device in Settings -> Account -> Manage two-factor authentication, and Register Universal Two-Factor (U2F) Device. After the usual Firefox Popup, and the light touch on the key button, that'it you have a fast, and reliable Two Factor Authentification !
ConclusionEach time I have to look on anything close to cryptography / authentification, it is a terminology avalanche. Here we had already 2FA, OTP, U2F, FIDO. And now there is FIDO2 too. It is the next version of the U2F standard, but this time it was named after the standardizing organization, FIDO. The web browser part of FIDO2 is called Webauthn. Also sometimes the whole FIDO2 is called Webauthn too. Easy to get, isn t it ?

Dima Kogan: org-babel for documentation

So I just gave a talk at SCaLE 18x about numpysane and gnuplotlib, two libraries I wrote to make using numpy bearable. With these two, it's actually quite nice! Prior to the talk I overhauled the documentation for both these projects. The gnuplotlib docs now have a tutorial/gallery page, which is interesting-enough to write about. Check it out! Mostly it is a sequence of Clearly you want the plots in the documentation to correspond to the code, so you want something to actually run each code snippet to produce each plot. Automatically. I don't want to maintain these manually, and periodically discover that the code doesn't make the plot I claim it does or worse: that the code barfs. This is vaguely what Jupyter notebooks do, but they're ridiculous, so I'm doing something better: That's it. The git repo is hosted by github, which has a rudimentary renderer for .org documents. I'm committing the .svg files, so that's enough to get rendered documentation that looks nice. Note that the usual workflow is to use org to export to html, but here I'm outsourcing that job to github; I just make the .svg files, and that's enough. Look at the link again: gnuplotlib tutorial/gallery. This is just a .org file committed to the git repo. github is doing its normal org->html thing to display this file. This has drawbacks too: github is ignoring the :noexport: tag on the init section at the end of the file, so it's actually showing all the emacs lisp goop that makes this work (described below!). It's at the end, so I guess this is good-enough. Those of us that use org-mode would be completely unsurprised to hear that the talk is also written as .org document. And the slides that show gnuplotlib plots use the same org-babel system to render the plots. It's all oh-so-nice. As with anything as flexible as org-babel, it's easy to get into a situation where you're bending it to serve a not-quite-intended purpose. But since this all lives in emacs, you can make it do whatever you want with a bit of emacs lisp. I ended up advising a few things (mailing list post here). And I stumbled on an (arguable) bug in emacs that needed working around (mailing list post here). I'll summarize both here.

Handling large Local Variables blocks
The advises I ended up with ended up longer than emacs expected, which made emacs not evaluate them when loading the buffer. As I discovered (see the mailing list post) the loading code looks for the string Local Variables in the last 3000 bytes of the buffer only, and I exceeded that. Stefan Monnier suggested a workaround in this post. Instead of the normal Local Variables block at the end: 
Local Variables:
eval: (progn ... ...
             ... ...
             LONG chunk of emacs-lisp
      )
End:
I do this: 
(progn ;;local-config
   lisp lisp lisp
   as long as I want
)
Local Variables:
eval: (progn (re-search-backward "^(progn ;;local-config") (eval (read (current-buffer))))
End:
So emacs sees a small chunk of code that searches backwards through the buffer (as far back as needed) for the real lisp to evaluate. As an aside, this blog is also an .org document, and the lisp snippets above are org-babel blocks that I'm not evaluating. The exporter knows to respect the emacs-lisp syntax highlighting, however.

Advises
OK, so what was all the stuff I needed to tell org-babel to do specially here? First off, org needed to be able to communicate to the Python session the name of the file to write the plot to. I do this by making the whole plist for this org-babel snippet available to python: 
;; THIS advice makes all the org-babel parameters available to python in the
;; _org_babel_params dict. I care about _org_babel_params['_file'] specifically,
;; but everything is available
(defun dima-org-babel-python-var-to-python (var)
  "Convert an elisp value to a python variable.
  Like the original, but supports (a . b) cells and symbols
"
  (if (listp var)
      (if (listp (cdr var))
          (concat "[" (mapconcat #'org-babel-python-var-to-python var ", ") "]")
        (format "\"\"\"%s\"\"\"" var))
    (if (symbolp var)
        (format "\"\"\"%s\"\"\"" var)
      (if (eq var 'hline)
          org-babel-python-hline-to
        (format
         (if (and (stringp var) (string-match "[\n\r]" var)) "\"\"%S\"\"" "%S")
         (if (stringp var) (substring-no-properties var) var))))))
(defun dima-alist-to-python-dict (alist)
  "Generates a string defining a python dict from the given alist"
  (let ((keyvalue-list
         (mapcar (lambda (x)
                   (format "%s = %s, "
                           (replace-regexp-in-string
                            "[^a-zA-Z0-9_]" "_"
                            (symbol-name (car x)))
                           (dima-org-babel-python-var-to-python (cdr x))))
                 alist)))
    (concat
     "dict( "
     (apply 'concat keyvalue-list)
     ")")))
(defun dima-org-babel-python-pass-all-params (f params)
  (cons
   (concat
    "_org_babel_params = "
    (dima-alist-to-python-dict params))
   (funcall f params)))
(unless
    (advice-member-p
     #'dima-org-babel-python-pass-all-params
     #'org-babel-variable-assignments:python)
  (advice-add
   #'org-babel-variable-assignments:python
   :around #'dima-org-babel-python-pass-all-params))
So if there's a :file plist key, the python code can grab that, and write the plot to that filename. But I don't really want to specify an output file for every single org-babel snippet. All I really care about is that each plot gets a unique filename. So I omit the :file key entirely, and use this advice to generate one for me: 
;; This sets a default :file tag, set to a unique filename. I want each demo to
;; produce an image, but I don't care what it is called. I omit the :file tag
;; completely, and this advice takes care of it
(defun dima-org-babel-python-unique-plot-filename
    (f &optional arg info params)
  (funcall f arg info
           (cons (cons ':file
                       (format "guide-%d.svg"
                               (condition-case nil
                                   (setq dima-unique-plot-number (1+ dima-unique-plot-number))
                                 (error (setq dima-unique-plot-number 0)))))
                 params)))
(unless
    (advice-member-p
     #'dima-org-babel-python-unique-plot-filename
     #'org-babel-execute-src-block)
  (advice-add
   #'org-babel-execute-src-block
   :around #'dima-org-babel-python-unique-plot-filename))
This uses the dima-unique-plot-number integer to keep track of each plot. I increment this with each plot. Getting closer. It isn't strictly required, but it'd be nice if each plot had the same output filename each time I generated it. So I want to reset the plot number to 0 each time: 
;; If I'm regenerating ALL the plots, I start counting the plots from 0
(defun dima-reset-unique-plot-number
    (&rest args)
    (setq dima-unique-plot-number 0))
(unless
    (advice-member-p
     #'dima-reset-unique-plot-number
     #'org-babel-execute-buffer)
  (advice-add
   #'org-babel-execute-buffer
   :after #'dima-reset-unique-plot-number))
Finally, I want to lie to the user a little bit. The code I'm actually executing writes each plot to an .svg. But the code I'd like the user to see should use the default output: an interactive, graphical window. I do that by tweaking the python session to tell the gnuplotlib object to write to .svg files from org by default, instead of using the graphical terminal: 
;; I'm using github to display guide.org, so I'm not using the "normal" org
;; exporter. I want the demo text to not contain the hardcopy= tags, but clearly
;; I need the hardcopy tag when generating the plots. I add some python to
;; override gnuplotlib.plot() to add the hardcopy tag somewhere where the reader
;; won't see it. But where to put this python override code? If I put it into an
;; org-babel block, it will be rendered, and the :export tags will be ignored,
;; since github doesn't respect those (probably). So I put the extra stuff into
;; an advice. Whew.
(defun dima-org-babel-python-set-demo-output (f body params)
  (with-temp-buffer
    (insert body)
    (beginning-of-buffer)
    (when (search-forward "import gnuplotlib as gp" nil t)
      (end-of-line)
      (insert
       "\n"
       "if not hasattr(gp.gnuplotlib, 'orig_init'):\n"
       "    gp.gnuplotlib.orig_init = gp.gnuplotlib.__init__\n"
       "gp.gnuplotlib.__init__ = lambda self, *args, **kwargs: gp.gnuplotlib.orig_init(self, *args, hardcopy=_org_babel_params['_file'] if 'file' in _org_babel_params['_result_params'] else None, **kwargs)\n"))
    (setq body (buffer-substring-no-properties (point-min) (point-max))))
  (funcall f body params))
(unless
    (advice-member-p
     #'dima-org-babel-python-set-demo-output
     #'org-babel-execute:python)
  (advice-add
   #'org-babel-execute:python
   :around #'dima-org-babel-python-set-demo-output))
)
And that's it. The advises in the talk are slightly different, in uninteresting ways. Some of this should be upstreamed to org-babel somehow. Now entirely clear which part, but I'll cross that bridge when I get to it.

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