Search Results: "jam"

6 June 2017

Reproducible builds folks: Reproducible Builds: week 110 in Stretch cycle

Here's what happened in the Reproducible Builds effort between Sunday May 28 and Saturday June 3 2017: Past an upcoming events Documentation updates Toolchain development and fixes Patches and bugs filed 4 package reviews have been added, 6 have been updated and 25 have been removed in this week, adding to our knowledge about identified issues. Weekly QA work During our reproducibility testing, FTBFS bugs have been detected and reported by: diffoscope development tests.reproducible-builds.org Mattia Rizzolo: Daniel Kahn Gillmor: Vagrant Cascadian: Holger Levsen: Misc. This week's edition was written by Chris Lamb, Bernhard M. Wiedemann and Holger Levsen & reviewed by a bunch of Reproducible Builds folks on IRC & the mailing lists.

Russ Allbery: Review: Star Healer

Review: Star Healer, by James White
Series: Sector General #6
Publisher: Orb
Copyright: 1984
Printing: 2002
ISBN: 0-312-87770-6
Format: Trade paperback
Pages: 206
Star Healer is the sixth book of the Sector General series, and I think it may be the first novel in the series that was written as a novel instead of a fix-up of short stories. That makes it not a bad place to start in the series if one would rather not deal with fix-ups or barely-disguised short story collections. There isn't a huge amount of character development over the course of this series (at least to this point), so the main thing you would lose by starting here is some built-up reason for caring about the main character. This is the third book in the Alien Emergencies omnibus (the book referenced in the publication information here). Most of the previous stories have focused on Conway, a Senior Physician in the sprawling and wonderfully well-equipped multi-species hospital called Sector General and, in recent stories, the head physician in the hospital's ambulance ship. Becoming a Senior Physician at Sector General is quite the accomplishment, and a fine point to reach in the career of any doctor specializing in varied life forms, but there is another tier above: the Diagnosticians, who are the elite of Sector General. The difference is education tapes. Deep knowledge of even one specific type of life is a lot to ask of a doctor, as shown by the increasing specialization of human medicine. Sector General, which deals with wildly varying ailments of thousands of species including entirely unknown ones (if, admittedly, primarily trauma, at least in the stories shown), would be an impossible task. White realizes this and works around it with education tapes that temporarily embed in a doctor's head the experience of a doctor of another species entirely. This provides the native expertise missing, but it comes with the full personality of the doctor who recorded the tape, including preferences for food and romantic attachment that may be highly disorienting. Senior Physicians use a tape at a time, and then have it erased again when they don't need it. Diagnosticians juggle four or more tapes at the same time, and keep them for long periods or even permanently, allowing them to do ground-breaking original research. The opening of Star Healer is an offer from the intimidating Chief Psychologist of Sector General: he has a shot at Diagnostician. But it's a major decision that he should think over first, so the next step is to take a vacation of sorts on a quiet world with a small human scientific station. Oh, and there's a native medical problem, although not one with much urgency. Conway doesn't do a lot of resting, because of course he gets pulled into trying to understand the mystery of an alien species that is solitary to the point of deep and unbreakable social taboos against even standing close to other people. This is a nice cultural puzzle in line with the rest of the series, but it also leaves Conway with a new ally: an alien healer in a society in which being a doctor is difficult to the point of near hopelessness. It's not much of a spoiler to say that of course Conway decides to try for Diagnostician after his "vacation." The rest of the book is him juggling multiple cases with his new and often conflicting modes of thinking, and tackling problems that require a bit less in the way of puzzle-solving and a bit more in the way of hard trade-off decisions and quick surgical action. Senior Physicians may be able to concentrate on just one puzzle at a time; Diagnosticians have to juggle several. And they're larger, more long-term problems, focusing on how to improve a general problem for a whole species rather than just heal a specific injured alien. One interesting aspect of this series, which is very much on display here, is that Sector General most definitely does not have a Prime Directive. They are cautious about making contact with particularly primitive civilizations for fear that spacefarers would give them an inferiority complex, but sometimes they do anyway. And if they run into some biological system that offends their sensibilities, they try to fix it, not just observe it. White frequently shows species caught in what the characters call "biological traps," unable to develop farther because of some biological adaptation that gets in their way, and Sector General tries to fix those. It's an interesting ethical problem that I wish they'd think about a bit more. It's not clear they're wrong, and I think it's correct to take an expansive view of the mission to heal, but there's also a sense in which Sector General is modifying culture and biology to make aliens more like them. (The parallels between this and all the abusive paternalism that human cultures do around disability is a little too close to home to be comfortable, and now I kind of wish it hadn't occurred to me.) The gender roles, sadly, continue to be dire, although mostly ignorable because the one major female character is generally just shown as another doctor with little attention to sex. But apparently women (of every species!) cannot become Diagnosticians because they have an insurmountable biological aversion to sharing their minds with a learning tape from any doctor who doesn't find them physically attractive, which is just... sigh. It's sad that someone who could write an otherwise remarkably open-minded and pacifist series of stories, in sharp contrast with most of SF history, would still have that large of a blind spot. Apart from the times gender comes up, I liked this book more than the rest of the series, in part because I strongly prefer novels to short stories. There's more room to develop the story, and while characterization continues to not be White's strong point and that space mostly goes to more puzzles instead, he does provide an interesting set of interlocking puzzles. The problem posed by the aliens Conway meets on his "vacation" isn't fully resolved here (presumably that's for a future book), but he does solve several other significant problems and develops his own problem-solving style in more depth than in previous stories. Mildly recommended, particularly if you like this series in general. Followed by Code Blue - Emergency. Rating: 7 out of 10

4 June 2017

Dirk Eddelbuettel: RcppArmadillo 0.7.900.2.0

armadillo image The new RcppArmadillo release 0.7.900.2.0 is now on CRAN, and the Debian package was just updated as well. Armadillo is a powerful and expressive C++ template library for linear algebra aiming towards a good balance between speed and ease of use with a syntax deliberately close to a Matlab. RcppArmadillo integrates this library with the R environment and language--and is widely used by (currently) 350 other packages on CRAN---an increase of 32 since the last CRAN release of 0.7.800.2.0 in April! With the 7.900.* series of Armadillo, Conrad has started to more fully utilize OpenMP (also see Wikipedia on OpenMP) for operations that can be parallelized. To use this in your package you need to update its src/Makevars ,.win file similarly to what the skeleton default now uses 
PKG_CXXFLAGS = $(SHLIB_OPENMP_CXXFLAGS) 
PKG_LIBS = $(SHLIB_OPENMP_CFLAGS) $(LAPACK_LIBS) $(BLAS_LIBS) $(FLIBS)
and you may want to enable C++11 while you are at it---though this may pose issues with older-than-ancient RHEL installations which are still (way too) pervasive so we do not do it by default (yet). Here, we once again rely on the build infrastructure automagically provided by R itself: if and when OpenMP is available, R will use it via $(SHLIB_OPENMP_CXXFLAGS) etc; see the fine WRE manual for details. That said, some operating systems make this harder than other, and macOS usually takes the crown. See for example this blog post by James for surviving in that environment. I am a little short of details because on Linux these things just work, and have for well over a decade. The rcpp-devel mailing list will be the best place for questions. Changes in this release relative to the previous CRAN release are as follows:

Changes in RcppArmadillo version 0.7.900.2.0 (2017-06-02)
  • Upgraded to Armadillo release 7.900.2 (Evil Banana Republic)
    • Expanded clamp() to handle cubes
    • Computationally expensive element-wise functions (such as exp(), log(), cos(), etc) can now be automatically sped up via OpenMP; this requires a C++11/C++14 compiler with OpenMP 3.0+ support for GCC and clang compilers
    • One caveat: when using GCC, use of -march=native in conjunction with -fopenmp may lead to speed regressions on recent processors
  • Added gcc 7 to support compiler check (James Balamuta in #128 addressing #126).
  • A unit test helper function for rmultinom was corrected (#133).
  • OpenMP support was added to the skeleton helper in inline.R

Courtesy of CRANberries, there is a diffstat report. More detailed information is on the RcppArmadillo page. Questions, comments etc should go to the rcpp-devel mailing list off the R-Forge page.

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

30 May 2017

Reproducible builds folks: Reproducible Builds: week 109 in Stretch cycle

Here's what happened in the Reproducible Builds effort between Sunday May 21 and Saturday May 27 2017: Past and upcoming events Bernhard M. Wiedemann gave a short talk on reproducible builds in openSUSE at the openSUSE Conference 2017. Slides and video recordings are available on that page. Chris Lamb will present at the Hong Kong Open Source Conference 2017 on reproducible builds on June 9th. Our next IRC meeting has been scheduled for Thursday June 1 at 16:00 UTC with this agenda. Academia Justin Cappos continued his work on the reproducible builds paper, with text and suggestions from Ximin Luo integrated. Toolchain developments #863470: "ftp.debian.org: security sync must not exclude .buildinfo" - while this bug isn't fixed, you need to make sure not to build jessie updates with stretch's dpkg, or else the upload will be rejected. Ximin Luo built GCC twice and ran diffoscope on them. Unfortunately the results were 1.7 GB in size and it can't be displayed in a web browser. 99/171 of the .debs are reproducible, though. He's now working on diffoscope (see below) to make it generate output more intelligently for such large size diffs. Here is a summary diff where the recursion depth cut-off was set low, so the size is reasonable and one can still see the outlines of where to look next. debuerreotype was newly added to Debian unstable. It is a reproducible, snapshot-based Debian rootfs builder. Patches and bugs filed Reviews of unreproducible packages 29 package reviews have been added, 49 have been updated and 23 have been removed in this week, adding to our knowledge about identified issues. Weekly QA work During our reproducibility testing, FTBFS bugs have been detected and reported by: diffoscope development Development continued in git, with commits from: strip-nondeterminism development Version 0.034-1 was uploaded to unstable by Chris Lamb. It included previous weeks' contributions from: tests.reproducible-builds.org: Misc. This week's edition was written by Ximin Luo, Bernhard M. Wiedemann, Chris Lamb and Holger Levsen & reviewed by a bunch of Reproducible Builds folks on IRC & the mailing lists.

27 May 2017

Russ Allbery: Optimistic haul

I never have as much time to read as I wish I did, but I keep buying books, of course. Maybe someday I'll have a good opportunity to take extended time off work and just read for a bit. Well, retirement, at least, right? Charlie Jane Anders All the Birds in the Sky (sff)
Peter C. Brown, et al. Make It Stick (nonfiction)
April Daniels Dreadnought: Nemesis (sff)
T. Kingfisher The Halcyon Fairy Book (sff collection)
T. Kingfisher Jackalope Wives and Other Stories (sff collection)
Margot Lee Shetterly Hidden Figures (nonfiction)
Cordwainer Smith Norstrilia (sff)
Kristine Smith Code of Conduct (sff)
Jonathan Taplin Move Fast and Break Things (nonfiction)
Sarah Zettel Fool's War (sff)
Sarah Zettel Playing God (sff)
Sarah Zettel The Quiet Invasion (sff) It doesn't help that James Nicoll keeps creating new lists of books that all sound great. And there's some really interesting nonfiction being written right now. Make It Stick is the current book for the work book club.

23 May 2017

Dirk Eddelbuettel: Rcpp 0.12.11: Loads of goodies

The elevent update in the 0.12.* series of Rcpp landed on CRAN yesterday following the initial upload on the weekend, and the Debian package and Windows binaries should follow as usual. The 0.12.11 release follows the 0.12.0 release from late July, the 0.12.1 release in September, the 0.12.2 release in November, the 0.12.3 release in January, the 0.12.4 release in March, the 0.12.5 release in May, the 0.12.6 release in July, the 0.12.7 release in September, the 0.12.8 release in November, the 0.12.9 release in January, and the 0.12.10.release in March --- making it the fifteenth release at the steady and predictable bi-montly release frequency. Rcpp has become the most popular way of enhancing GNU R with C or C++ code. As of today, 1026 packages on CRAN depend on Rcpp for making analytical code go faster and further, along with another 91 in BioConductor. This releases follows on the heels of R's 3.4.0 release and addresses on or two issues from the transition, along with a literal boatload of other fixes and enhancements. James "coatless" Balamuta was once restless in making the documentation better, Kirill Mueller addressed a number of more obscure compiler warnings (triggered under under -Wextra and the like), Jim Hester improved excecption handling, and much more mostly by the Rcpp Core team. All changes are listed below in some detail. One big change that JJ made is that Rcpp Attributes also generate the now-almost-required package registration. (For background, I blogged about this one, two, three times.) We tested this, and do not expect it to throw curveballs. If you have an existing src/init.c, or if you do not have registration set in your NAMESPACE. It should cover most cases. But one never knows, and one first post-release buglet related to how devtools tests things has already been fixed in this PR by JJ.

Changes in Rcpp version 0.12.11 (2017-05-20)
  • Changes in Rcpp API:
    • Rcpp::exceptions can now be constructed without a call stack (Jim Hester in #663 addressing #664).
    • Somewhat spurious compiler messages under very verbose settings are now suppressed (Kirill Mueller in #670, #671, #672, #687, #688, #691).
    • Refreshed the included tinyformat template library (James Balamuta in #674 addressing #673).
    • Added printf-like syntax support for exception classes and variadic templating for Rcpp::stop and Rcpp::warning (James Balamuta in #676).
    • Exception messages have been rewritten to provide additional information. (James Balamuta in #676 and #677 addressing #184).
    • One more instance of Rf_mkString is protected from garbage collection (Dirk in #686 addressing #685).
    • Two exception specification that are no longer tolerated by g++-7.1 or later were removed (Dirk in #690 addressing #689)
  • Changes in Rcpp Documentation:
  • Changes in Rcpp Sugar:
    • Added sugar function trimws (Nathan Russell in #680 addressing #679).
  • Changes in Rcpp Attributes:
    • Automatically generate native routine registrations (JJ in #694)
    • The plugins for C++11, C++14, C++17 now set the values R 3.4.0 or later expects; a plugin for C++98 was added (Dirk in #684 addressing #683).
  • Changes in Rcpp support functions:
    • The Rcpp.package.skeleton() function now creates a package registration file provided R 3.4.0 or later is used (Dirk in #692)

Thanks to CRANberries, you can also look at a diff to the previous release. As always, even fuller details are on the Rcpp Changelog page and the Rcpp page which also leads to the downloads page, the browseable doxygen docs and zip files of doxygen output for the standard formats. A local directory has source and documentation too. Questions, comments etc should go to the rcpp-devel mailing list off the R-Forge page.

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

21 May 2017

Russ Allbery: Review: Sector General

Review: Sector General, by James White
Series: Sector General #5
Publisher: Orb
Copyright: 1983
Printing: 2002
ISBN: 0-312-87770-6
Format: Trade paperback
Pages: 187
Sector General is the fifth book (or, probably more accurately, collection) in the Sector General series. I blame the original publishers for the confusion. The publication information is for the Alien Emergencies omnibus, which includes the fourth through the sixth books in the series. Looking back on my previous reviews of this series (wow, it's been eight years since I read the last one?), I see I was reviewing them as novels rather than as short story collections. In retrospect, that was a mistake, since they're composed of clearly stand-alone stories with a very loose arc. I'm not going to go back and re-read the earlier collections to give them proper per-story reviews, but may as well do this properly here. Overall, this collection is more of the same, so if that's what you want, there won't be any negative surprises. It's another four engineer-with-a-wrench stories about biological and medical puzzles, with only a tiny bit of characterization and little hint to any personal life for any of the characters outside of the job. Some stories are forgettable, but White does create some memorable aliens. Sadly, the stories don't take us to the point of real communication, so those aliens stop at biological puzzles and guesswork. "Combined Operation" is probably the best, although "Accident" is the most philosophical and an interesting look at the founding principle of Sector General. "Accident": MacEwan and Grawlya-Ki are human and alien brought together by a tragic war, and forever linked by a rather bizarre war monument. (It's a very neat SF concept, although the implications and undiscussed consequences don't bear thinking about too deeply.) The result of that war was a general recognition that such things should not be allowed to happen again, and it brought about a new, deep commitment to inter-species tolerance and politeness. Which is, in a rather fascinating philosophical twist, exactly what MacEwan and Grawlya-Ki are fighting against: not the lack of aggression, which they completely agree with, but with the layers of politeness that result in every species treating all others as if they were eggshells. Their conviction is that this cannot create a lasting peace. This insight is one of the most profound bits I've read in the Sector General novels and supports quite a lot of philosophical debate. (Sadly, there isn't a lot of that in the story itself.) The backdrop against which it plays out is an accidental crash in a spaceport facility, creating a dangerous and potentially deadly environment for a variety of aliens. Given the collection in which this is included and the philosophical bent described above, you can probably guess where this goes, although I'll leave it unspoiled if you can't. It's an idea that could have been presented with more subtlety, but it's a really great piece of setting background that makes the whole series snap into focus. A much better story in context than its surface plot. (7) "Survivor": The hospital ship Rhabwar rescues a sole survivor from the wreck of an alien ship caused by incomplete safeguards on hyperdrive generators. The alien is very badly injured and unconscious and needs the full attention of Sector General, but on the way back, the empath Prilicla also begins suffering from empathic hypersensitivity. Conway, the protagonist of most of this series, devotes most of his attention to that problem, having delivered the rescued alien to competent surgical hands. But it will surprise no regular reader that the problems turn out to be linked (making it a bit improbable that it takes the doctors so long to figure that out). A very typical entry in the series. (6) "Investigation": Another very typical entry, although this time the crashed spaceship is on a planet. The scattered, unconscious bodies of the survivors, plus signs of starvation and recent amputation on all of them, convinces the military (well, police is probably more accurate) escort that this is may be a crime scene. The doctors are unconvinced, but cautious, and local sand storms and mobile vegetation add to the threat. I thought this alien design was a bit less interesting (and a lot creepier). (6) "Combined Operation": The best (and longest) story of this collection. Another crashed alien spacecraft, but this time it's huge, large enough (and, as they quickly realize, of a design) to indicate a space station rather than a ship, except that it's in the middle of nowhere and each segment contains a giant alien worm creature. Here, piecing together the biology and the nature of the vehicle is only the beginning; the conclusion points to an even larger problem, one that requires drawing on rather significant resources to solve. (On a deadline, of course, to add some drama.) This story requires the doctors to go unusually deep into the biology and extrapolated culture of the alien they're attempting to rescue, which made it more intellectually satisfying for me. (7) Followed by Star Healer. Rating: 6 out of 10

19 May 2017

Benjamin Mako Hill: Children s Perspectives on Critical Data Literacies

Last week, we presented a new paper that describes how children are thinking through some of the implications of new forms of data collection and analysis. The presentation was given at the ACM CHI conference in Denver last week and the paper is open access and online. Over the last couple years, we ve worked on a large project to support children in doing and not just learning about data science. We built a system, Scratch Community Blocks, that allows the 18 million users of the Scratch online community to write their own computer programs in Scratch of course to analyze data about their own learning and social interactions. An example of one of those programs to find how many of one s follower in Scratch are not from the United States is shown below. Last year, we deployed Scratch Community Blocks to 2,500 active Scratch users who, over a period of several months, used the system to create more than 1,600 projects. As children used the system, Samantha Hautea, a student in UW s Communication Leadership program, led a group of us in an online ethnography. We visited the projects children were creating and sharing. We followed the forums where users discussed the blocks. We read comment threads left on projects. We combined Samantha s detailed field notes with the text of comments and forum posts, with ethnographic interviews of several users, and with notes from two in-person workshops. We used a technique called grounded theory to analyze these data. What we found surprised us. We expected children to reflect on being challenged by and hopefully overcoming the technical parts of doing data science. Although we certainly saw this happen, what emerged much more strongly from our analysis was detailed discussion among children about the social implications of data collection and analysis. In our analysis, we grouped children s comments into five major themes that represented what we called critical data literacies. These literacies reflect things that children felt were important implications of social media data collection and analysis. First, children reflected on the way that programmatic access to data even data that was technically public introduced privacy concerns. One user described the ability to analyze data as, creepy , but at the same time, very cool. Children expressed concern that programmatic access to data could lead to stalking and suggested that the system should ask for permission. Second, children recognized that data analysis requires skepticism and interpretation. For example, Scratch Community Blocks introduced a bug where the block that returned data about followers included users with disabled accounts. One user, in an interview described to us how he managed to figure out the inconsistency:

At one point the follower blocks, it said I have slightly more followers than I do. And, that was kind of confusing when I was trying to make the project. [ ] I pulled up a second [browser] tab and compared the [data from Scratch Community Blocks and the data in my profile]. Third, children discussed the hidden assumptions and decisions that drive the construction of metrics. For example, the number of views received for each project in Scratch is counted using an algorithm that tries to minimize the impact of gaming the system (similar to, for example, Youtube). As children started to build programs with data, they started to uncover and speculate about the decisions behind metrics. For example, they guessed that the view count might only include unique views and that view counts may include users who do not have accounts on the website. Fourth, children building projects with Scratch Community Blocks realized that an algorithm driven by social data may cause certain users to be excluded. For example, a 13-year-old expressed concern that the system could be used to exclude users with few social connections saying:

I love these new Scratch Blocks! However I did notice that they could be used to exclude new Scratchers or Scratchers with not a lot of followers by using a code: like this:
when flag clicked
if then user s followers < 300
stop all.
I do not think this a big problem as it would be easy to remove this code but I did just want to bring this to your attention in case this not what you would want the blocks to be used for.
Fifth, children were concerned about the possibility that measurement might distort the Scratch community s values. While giving feedback on the new system, a user expressed concern that by making it easier to measure and compare followers, the system could elevate popularity over creativity, collaboration, and respect as a marker of success in Scratch.

I think this was a great idea! I am just a bit worried that people will make these projects and take it the wrong way, saying that followers are the most important thing in on Scratch. Kids conversations around Scratch Community Blocks are good news for educators who are starting to think about how to engage young learners in thinking critically about the implications of data. Although no kid using Scratch Community Blocks discussed each of the five literacies described above, the themes reflect starting points for educators designing ways to engage kids in thinking critically about data. Our work shows that if children are given opportunities to actively engage and build with social and behavioral data, they might not only learn how to do data analysis, but also reflect on its implications.

This blog-post and the work that it describes is a collaborative project by Samantha Hautea, Sayamindu Dasgupta, and Benjamin Mako Hill. We have also received support and feedback from members of the Scratch team at MIT (especially Mitch Resnick and Natalie Rusk), as well as from Hal Abelson from MIT CSAIL. Financial support came from the US National Science Foundation.

17 May 2017

Jamie McClelland: Late to the Raspberry Pi party

I finally bought my first raspberry pi to setup as a router and wifi access point. It wasn't easy. I first had to figure out what to buy. I think that was the hardest part. I ended up with: I already have a cable matters USB to ethernet device, which will provide the second ethernet connection so this device can actually work as a router. I studiously followed the directions to download the raspbian image and copy it to my micro sd card. I also touched a file on the boot partition called ssh so ssh would start automatically. Note: I first touched the ssh file on the root partition (sdb2) before realizing it belonged on the boot partition (sdb1). And, despite ambiguous directions found on the Internet, lowercase 'ssh' for the filename seems to do the trick. Then, I found the IP address with the help of NMAP (sudo nmap -sn 192.168.69.*) and tried to ssh in but alas... 
Connection reset by 192.168.69.116 port 22
No dice. So, I re-mounted the sdb2 partition of the micro sd card and looked in var/log/auth.log and found: 
May  5 19:23:00 raspberrypi sshd[760]: error: Could not load host key: /etc/ssh/ssh_host_ed25519_key
May  5 19:23:00 raspberrypi sshd[760]: fatal: No supported key exchange algorithms [preauth]
May  5 19:23:07 raspberrypi sshd[762]: error: key_load_public: invalid format
May  5 19:23:07 raspberrypi sshd[762]: error: Could not load host key: /etc/ssh/ssh_host_rsa_key
May  5 19:23:07 raspberrypi sshd[762]: error: key_load_public: invalid format
May  5 19:23:07 raspberrypi sshd[762]: error: Could not load host key: /etc/ssh/ssh_host_dsa_key
May  5 19:23:07 raspberrypi sshd[762]: error: key_load_public: invalid format
May  5 19:23:07 raspberrypi sshd[762]: error: Could not load host key: /etc/ssh/ssh_host_ecdsa_key
May  5 19:23:07 raspberrypi sshd[762]: error: key_load_public: invalid format
How did that happen? And wait a minute... 
0 jamie@turkey:~$ ls -l /mnt/etc/ssh/ssh_host_ecdsa_key
-rw------- 1 root root 0 Apr 10 05:58 /mnt/etc/ssh/ssh_host_ecdsa_key
0 jamie@turkey:~$ date
Fri May  5 15:44:15 EDT 2017
0 jamie@turkey:~$
Are the keys embedded in the image? Isn't that wrong? I fixed with: 
0 jamie@turkey:mnt$ sudo rm /mnt/etc/ssh/ssh_host_*
0 jamie@turkey:mnt$ sudo ssh-keygen -q -f /mnt/etc/ssh/ssh_host_rsa_key -N '' -t rsa
0 jamie@turkey:mnt$ sudo ssh-keygen -q -f /mnt/etc/ssh/ssh_host_dsa_key -N '' -t dsa
0 jamie@turkey:mnt$ sudo ssh-keygen -q -f /mnt/etc/ssh/ssh_host_ecdsa_key -N '' -t ecdsa
0 jamie@turkey:mnt$ sudo ssh-keygen -q -f /mnt/etc/ssh/ssh_host_ed25519_key -N '' -t ed25519
0 jamie@turkey:mnt$
NOTE: I just did a second installation and this didn't happen. Maybe something went wrong as I experiment with SSH vs ssh on the boot partition? Then I could ssh in. I removed the pi user account and added my ssh key to /root/.ssh/authorized_keys and put a new name "mondragon" in the /etc/hostname file. And... I upgraded to Debian stretch and rebooted. Then, I followed these instructions for fixing the wifi (replacing the firmware does still work for me). I plugged my cable matters USB/Ethernet adapter into the device so it would be recognized, but left it dis-connected. Next I started to configure the device to be a wifi access point using this excellend tutorial, but decided I wanted to setup my networks using systemd-networkd instead. Since /etc/network/interaces already had eth0 set to manual (because apparently it is controlled by dhcpcd instead), I didn't need any modifications there. However, I wanted to use the dhcp client built-in to systemd-networkd, so to prevent dhcpcd from obtaining an IP address, I purged dhcpcd: 
apt-get purge dhcpcd5
I was planning to also use systemd-networkd to name the devices (using *.link files) but nothing I could do could convince systemd to rename them, so I gave up and added /etc/udev/rules.d/70-persistent-net.rules: 
    SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR address =="b8:27:eb:ce:b5:c3", ATTR dev_id =="0x0", ATTR type =="1", NAME:="wan"
    SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR address =="a0:ce:c8:01:20:7d", ATTR dev_id =="0x0", ATTR type =="1", NAME:="lan"
    SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR address =="b8:27:eb:9b:e0:96", ATTR dev_id =="0x0", ATTR type =="1", NAME:="wlan"
(If you are copying and pasting the mac addresses will have to change.) Then I added the following files: 
root@mondragon:~# head /etc/systemd/network/*
==> /etc/systemd/network/50-lan.network <==
[Match]
Name=lan
[Network]
Address=192.168.69.1/24
==> /etc/systemd/network/55-wlan.network <==
[Match]
Name=wlan
[Network]
Address=10.0.69.1/24
==> /etc/systemd/network/60-wan.network <==
[Match]
Name=wan
[Network]
DHCP=v4
IPForward=yes
IPMasquerade=yes
root@mondragon:~#
Sadly, IPMasquerade doesn't seem to work either for some reason, so... 
root@mondragon:~# cat /etc/systemd/system/masquerade.service 
[Unit]
Description=Start masquerading because Masquerade=yes not working in wan.network.
[Service]
Type=oneshot
ExecStart=/sbin/iptables -t nat -A POSTROUTING -o wan -j MASQUERADE
[Install]
WantedBy=network.target
root@mondragon:~#
And, systemd DHCPServer worked, but then it didn't and I couldn't figure out how to debug, so... 
apt-get install dnsmasq
Followed by: 
root@mondragon:~# cat /etc/dnsmasq.d/mondragon.conf 
# Don't provide DNS services (unbound does that).
port=0
interface=lan
interface=wlan
# Only provide dhcp services since systemd-networkd dhcpserver seems
# flakey.
dhcp-range=set:cable,192.168.69.100,192.168.69.150,255.255.255.0,4h
dhcp-option=tag:cable,option:dns-server,192.168.69.1
dhcp-option=tag:cable,option:router,192.168.69.1
dhcp-range=set:wifi,10.0.69.100,10.0.69.150,255.255.255.0,4h
dhcp-option=tag:wifi,option:dns-server,10.0.69.1
dhcp-option=tag:wifi,option:router,10.0.69.1
root@mondragon:~#
It would probably be simpler to have dnsmasq provide DNS service also, but I happen to like unbound: 
apt-get install unbound
And... 
root@mondragon:~# cat /etc/unbound/unbound.conf.d/server.conf 
server:
    interface: 127.0.0.1
    interface: 192.168.69.1
    interface: 10.0.69.1
    access-control: 192.168.69.0/24 allow
    access-control: 10.0.69.0/24 allow
    # We do query localhost for our stub zone: loc.cx
    do-not-query-localhost: no
    # Up this level when debugging.
    log-queries: no
    logfile: ""
    #verbosity: 1
    # Settings to work better with systemcd
    do-daemonize: no
    pidfile: ""
root@mondragon:~#
Now on to the wifi access point. 
apt-get install hostapd
And the configuration file: 
root@mondragon:~# cat /etc/hostapd/hostapd.conf
# This is the name of the WiFi interface we configured above
interface=wlan
# Use the nl80211 driver with the brcmfmac driver
driver=nl80211
# This is the name of the network
ssid=peacock
# Use the 2.4GHz band
hw_mode=g
# Use channel 6
channel=6
# Enable 802.11n
ieee80211n=1
# Enable WMM
wmm_enabled=1
# Enable 40MHz channels with 20ns guard interval
ht_capab=[HT40][SHORT-GI-20][DSSS_CCK-40]
# Accept all MAC addresses
macaddr_acl=0
# Use WPA authentication
auth_algs=1
# Require clients to know the network name
ignore_broadcast_ssid=0
# Use WPA2
wpa=2
# Use a pre-shared key
wpa_key_mgmt=WPA-PSK
# The network passphrase
wpa_passphrase=xxxxxxxxxxxx
# Use AES, instead of TKIP
rsn_pairwise=CCMP
root@mondragon:~#
The hostapd package doesn't have a systemd start up file so I added one: 
root@mondragon:~# cat /etc/systemd/system/hostapd.service 
[Unit]
Description=Hostapd IEEE 802.11 AP, IEEE 802.1X/WPA/WPA2/EAP/RADIUS Authenticator
Wants=network.target
Before=network.target
Before=network.service
[Service]
ExecStart=/usr/sbin/hostapd /etc/hostapd/hostapd.conf
[Install]
WantedBy=multi-user.target
root@mondragon:~#
My last step was to modify /etc/ssh/sshd_config so it only listens on the lan and wlan interfaces (listening on wlan is a bit of a risk, but also useful when mucking with the lan network settings to ensure I don't get locked out).

15 May 2017

Gunnar Wolf: Starting a project on private and anonymous network usage

I am starting a work with the students of LIDSOL (Laboratorio de Investigaci n y Desarrollo de Software Libre, Free Software Research and Development Laboratory) of the Engineering Faculty of UNAM:

We want to dig into the technical and social implications of mechanisms that provide for anonymous, private usage of the network. We will have our first formal work session this Wednesday, for which we have invited several interesting people to join the discussion and help provide a path for our oncoming work. Our invited and confirmed guests are, in alphabetical order:

10 May 2017

Jonathan Dowland: Three things I didn't know about Haskell

I've been trying to refresh my Haskell skills and Paul Callaghan recommended I read the paper "A History of Haskell: Being Lazy With Class", which I found (surprisingly?) fascinating. Three facts about Haskell that I didn't know jumped out at me:

9 May 2017

Benjamin Mako Hill: Surviving an Eternal September: How an Online Community Managed a Surge of Newcomers

Attracting newcomers is among the most widely studied problems in online community research. However, with all the attention paid to challenge of getting new users, much less research has studied the flip side of that coin: large influxes of newcomers can pose major problems as well! The most widely known example of problems caused by an influx of newcomers into an online community occurred in Usenet. Every September, new university students connecting to the Internet for the first time would wreak havoc in the Usenet discussion forums. When AOL connected its users to the Usenet in 1994, it disrupted the community for so long that it became widely known as The September that never ended . Our study considered a similar influx in NoSleep an online community within Reddit where writers share original horror stories and readers comment and vote on them. With strict rules requiring that all members of the community suspend disbelief, NoSleep thrives off the fact that readers experience an immersive storytelling environment. Breaking the rules is as easy as questioning the truth of someone s story. Socializing newcomers represents a major challenge for NoSleep.
Number of subscribers and moderators on /r/NoSleep over time.
On May 7th, 2014, NoSleep became a default subreddit i.e., every new user to Reddit automatically joined NoSleep. After gradually accumulating roughly 240,000 members from 2010 to 2014, the NoSleep community grew to over 2 million subscribers in a year. That said, NoSleep appeared to largely hold things together. This reflects the major question that motivated our study: How did NoSleep withstand such a massive influx of newcomers without enduring their own Eternal September? To answer this question, we interviewed a number of NoSleep participants, writers, moderators, and admins. After transcribing, coding, and analyzing the results, we proposed that NoSleep survived because of three inter-connected systems that helped protect the community s norms and overall immersive environment. First, there was a strong and organized team of moderators who enforced the rules no matter what. They recruited new moderators knowing the community s population was going to surge. They utilized a private subreddit for NoSleep s staff. They were able to socialize and educate new moderators effectively. Although issuing sanctions against community members was often difficult, our interviewees explained that NoSleep s moderators were deeply committed and largely uncompromising. That commitment resonates within the second system that protected NoSleep: regulation by normal community members. From our interviews, we found that the participants felt a shared sense of community that motivated them both to socialize newcomers themselves as well as to report inappropriate comments and downvote people who violate the community s norms. Finally, we found that the technological systems protected the community as well. For instance, post-throttling was instituted to limit the frequency at which a writer could post their stories. Additionally, Reddit s Automoderator , a programmable AI bot, was used to issue sanctions against obvious norm violators while running in the background. Participants also pointed to the tools available to them the report feature and voting system in particular to explain how easy it was for them to report and regulate the community s disruptors.

This blog post was written with Charlie Kiene. The paper and work this post describes is collaborative work with Charlie Kiene and Andr s Monroy-Hern ndez. The paper was published in the Proceedings of CHI 2016 and is released as open access so anyone can read the entire paper here. A version of this post was published on the Community Data Science Collective blog.

8 May 2017

Mike Gabriel: [Arctica Project] Release of nx-libs (version 3.5.99.7)

Introduction NX is a software suite which implements very efficient compression of the X11 protocol. This increases performance when using X applications over a network, especially a slow one. NX (v3) has been originally developed by NoMachine and has been Free Software ever since. Since NoMachine obsoleted NX (v3) some time back in 2013/2014, the maintenance has been continued by a versatile group of developers. The work on NX (v3) is being continued under the project name "nx-libs". Release Announcement On Friday, May 5th 2017, version 3.5.99.7 of nx-libs has been released [1]. Credits A special thanks goes to Ulrich Sibiller for tracking down a regression bug that caused a tremendously slowed down keyboard input on high latency connections. Thanks for that! Another thanks goes to the Debian project for indirectly providing us with so many build platforms. We are nearly at the point where nx-libs builds on all architectures supported by the Debian project. (Runtime stability is a completely different issue, we will get to this soon). Changes between 3.5.99.6 and 3.5.99.7 Change Log The complete list of changes (since 3.5.99.6) can be obtained from here. Known Issues A list of known issues can be obtained from the nx-libs issue tracker [issues]. Binary Builds You can obtain binary builds of nx-libs for Debian (jessie, stretch, unstable) and Ubuntu (trusty, xenial) via these apt-URLs: Our package server's archive key is: 0x98DE3101 (fingerprint: 7A49 CD37 EBAE 2501 B9B4 F7EA A868 0F55 98DE 3101). Use this command to make APT trust our package server: 
 wget -qO - http://packages.arctica-project.org/archive.key   sudo apt-key add -
The nx-libs software project brings to you the binary packages nxproxy (client-side component) and nxagent (nx-X11 server, server-side component). The nxagent Xserver can be used from remote sessions (via nxcomp compression library) or as a next Xserver. Ubuntu developers, please note: we have added nightly builds for Ubuntu latest to our build server. At the moment, you can obtain nx-libs builds for Ubuntu 16.10 (yakkety) and 17.04 (zenial) as nightly builds. References

3 May 2017

Ingo Juergensmann: Back to the roots: FidoNet

Back in the good old days there was no Facebook, Google+, Skype and no XMPP servers for people to communicate with each other. The first "social communities" were Bulletin Board Systems (BBS), if you want to see those as social communities. Often those BBS not only offered communication possibilities to online users but also ways to communicate with others when being offline. Being offline is from todays point of view a strange concept, but back then it was a common scenario 20-30 years ago, because being online meant to dial via a modem and a phone line into a BBS or - at a later time - Internet provider. Those BBS interconnected with each others and some networks grew that allowed to exchange messages between different BBS - or mailboxes. One of those networks was FidoNet. When I went "online" back then, I called into a BBS, a mailbox. I don't know why, but when reading messages from others the mailbox crashed quite frequently. So the "sysop" of that mailbox offered me to become a FidoNet point - just to prevent that I'd keep crashing his mailbox all the time. So, there I was: a FidoNet point, reachable under the FidoNet address 2:2449/413.19. At some time I took over the mailbox from the old sysop, because he moved out of town. Despite the fact that the Internet arose in the late 1990s, making all those BBS, mailboxes, and networks such as FidoNet obsolete. However, it was a whole lot of fun back then. So much fun that I plan to join FidoNet again. Yes, it's still there! Instead of using dial-up connections via modems most nodes in FidoNet now offers connection via Internet as well. A FidoNet system (node) usually consists of a mailer that does the exchange with other systems, a tosser that "routes" the mail to the recipients, and a reader with which you can finally read and write messages to others. Back in the old days I ran my mailbox on my Amiga 3000 with a Zyxel U-1496E+ modem, later with an ISDN card called ISDN-Master. The software used was first TrapDoor as mailer and TrapToss as a tosser. Later replaced by GMS Mailer as a mailer and MailManager as a tosser and reader. Unfortunately GMS Mailer is not able to handle connections via Internet. For this you'll need something like binkd, which is a Debian package. So, doing a quick search for FidoNet packages on Debian reveals this:
# apt-cache search fidonets 0.00 % 0.00 % [kdevtmpfs]
crashmail - JAM and *.MSG capable Fidonet tosser
fortunes-es - Spanish fortune database
htag - A tagline/.signature adder for email, news and FidoNet messages
ifcico - Fidonet Technology transport package
ifgate - Internet to Fidonet gateway
ifmail - Internet to Fidonet gateway
jamnntpd - NNTP Server allowing newsreaders to access a JAM messagebase
jamnntpd-dbg - debugging symbols for jamnntpd
lbdb - Little Brother's DataBase for the mutt mail reader
So, there are at least two different mailer (ifcico and binkd) and crashmail as a tosser. What is missing is a FidoNet reader. In older Debian releases there was GoldEd+, but this package got removed from Debian some years ago. There's still some upstream development of GoldEd+, but when I tried to compile it fails. So there is no easy way to have a full FidoNet node running on Debian, which is sad. Yes, FidoNet is maybe outdated technology, but it's still alive and I would like to get a FidoNet node running again. Are there any other FidoNet nodes running on Debian and give assistance in setting up? There are maybe some fully integrated solutions like MysticBBS, but I'm unsure about those. So, any tips and hints are welcome! :-)
Kategorie:
Debian
Tags:
Debian
Software
Fidonet

11 April 2017

Antoine Beaupr : A report from Netconf: Day 1

As is becoming traditional, two times a year the kernel networking community meets in a two-stage conference: an invite-only, informal, two-day plenary session called Netconf, held in Toronto this year, and a more conventional one-track conference open to the public called Netdev. I was invited to cover both conferences this year, given that Netdev was in Montreal (my hometown), and was happy to meet the crew of developers that maintain the network stack of the Linux kernel. This article covers the first day of the conference which consisted of around 25 Linux developers meeting under the direction of David Miller, the kernel's networking subsystem maintainer. Netconf has no formal sessions; although some people presented slides, interruptions are frequent (indeed, encouraged) and the focus is on hashing out issues that are blocked on the mailing list and getting suggestions, ideas, solutions, and feedback from their peers.

Removing ndo_select_queue() One of the first discussions that elicited a significant debate was the ndo_select_queue() function, a key component of the Linux polling system that determines when and how to send packets on a network interface (see netdev_pick_tx and friends). The general question was whether the use of ndo_select_queue() in drivers is a good idea. Alexander Duyck explained that Intel people were considering using ndo_select_queue() for receive/transmit queue matching. Intel drivers do not currently use the hook provided by the Linux kernel and it turns out no one is happy with ndo_select_queue(): the heuristics it uses don't really please anyone. The consensus (including from Duyck himself) seemed to be that it should just not be used anymore, or at least not used for that specific purpose. The discussion turned toward the wireless network stack, which uses it extensively, but for other purposes. Johannes Berg explained that the wireless stack uses ndo_select_queue() for traffic classification, for example to get voice traffic through even if the best-effort queue is backed up. The wireless stack could stop using it by doing flow control completely inside the wireless stack, which already uses the fq_codel flow-control mechanism for other purposes, so porting away from ndo_select_queue() seems possible there. The problem then becomes how to update all the drivers to change that behavior, which would be a lot of work. Still, it seems people are moving away from a generic ndo_select_queue() interface to stack-specific or even driver-specific (in the case of Intel) queue management interfaces.

refcount_t followup There was a followup discussion on the integration of the refcount_t type into the network stack, which we covered recently. This type is meant to be an in-kernel defense against exploits based on overflowing or underflowing an object's reference count. The consensus seems to be that having refcount_t used for debugging is acceptable, but it cannot be enabled by default. An issue that was identified is that the networking developers are fairly sure that introducing refcount_t would have a severe impact on performance, but they do not have benchmarks to prove it, something Miller identified as a problem that needs to be worked on. Miller then expressed some openness to the idea of having it as a kernel configuration option. A similar discussion happened, on the second day, regarding the KASan memory error detector which was covered when it was introduced in 2014. Eric Dumazet warned that there could be a lot of issues that cannot be detected by KASan because of the way the network stack often bypasses regular memory-allocation routines for performance reasons. He also noted that this can sometimes mean the stack may go over the regular 10% memory limit (the tcp_mem parameter, described in the tcp(7) man page) for certain operations, especially when rebuilding out of order packets with lots of parallel TCP connections. Therefore it was proposed that these special memory recycling tricks could be optionally disabled, at run or compile-time, to instrument proper memory tracking. Dumazet argued this was a situation similar to refcount_t in that we need a way to disable high performance to make the network stack easier to debug with KAsan. The problem with optional parameters is that they are often disabled in production or even by default, which, in turn, means that critical bugs cannot actually be found because the code paths are not tested. When I asked Dumazet about this, he explained that Google performs integration testing of new kernels before putting them in production, and those toggles could be enabled there to find and fix those bugs. But he agreed that certain code paths are then not tested until the code gets deployed in production. So it seems the status quo remains: security folks wants to improve the reliability of the kernel, but the network folks can't afford the performance cost. Yet it was clear in the discussions that the team cares about security issues and wants those issues to be fixed; the impact of some of the solutions is just too big.

Lightweight wireless management packet access Berg explained that some users need to have high-performance access to certain management frames in the wireless stack and wondered how to best expose those to user space. The wireless stack already allows users to clone a network interface in "monitor" mode, but this has a big performance cost, as the radiotap header needs to be constructed from scratch and the packet header needs to be copied. As wireless improves and the bandwidth rises to gigabit levels, this can become significant bottleneck for packet sniffers or reporting software that need to know precisely what's going on over the air outside of the regular access point client operation. It seems the proper way to do this is with an eBPF program. As Miller summarized, just add another API call that allows loading a BPF program into the kernel and then those users can use a BPF filtering point to get the statistics they need. This will require an extra hook in the wireless stack, but it seems like this is the way that will be taken to implement this feature.

VLAN 0 inconsistencies Hannes Frederic Sowa brought up the seemingly innocuous question of "how do we handle VLAN 0?" In theory, VLAN 0 means "no VLAN". But the Linux kernel currently handles this differently depending on whether the VLAN module is loaded and whether a VLAN 0 interface was created. Sometimes the VLAN tag is stripped, sometimes not. It turns out the semantics of this were accidentally changed last time there was a change here and this was originally working but is now broken. Sowa therefore got the go-ahead to fix this to make the behavior consistent again.

Loopy fun Then it came the turn of Jamal Hadi Salim, the maintainer of the kernel's traffic-control (tc) subsystem. The first issue he brought up is a problem in the tc REDIRECT action that can create infinite loops within the kernel. The problem can be easily alleviated when loops are created on the same interface: checks can be added that just drop packets coming from the same device and rate-limit logging to avoid a denial-of-service (DoS) condition. The more serious problem occurs when a packet is forwarded from (say) interface eth0 to eth1 which then promptly redirects it from eth1 back to eth0. Obviously, this kind of problem can only be created by a user with root access so, at first glance, those issues don't seem that serious: admins can shoot themselves in the foot, so what? But things become a little more serious when you consider the container case, where an untrusted user has root access inside a container and should have constrained resource limitations. Such a loop could allow this user to deploy an effective DoS attack against a whole group of containers running on the same machine. Even worse, this endless loop could possibly turn into a deadlock in certain scenarios, as the kernel could try to transmit the packet on the same device it originated from and block, progressively filling the queues and eventually completely breaking network access. Florian Westphal argued that a container can already create DoS conditions, for example by doing a ping flood. According to Salim, this whole problem was created when two bits used for tracking such packets were reclaimed from the skb structure used to represent packets in the kernel. Those bits were a simple TTL (time to live) field that was incremented on each loop and dropped after a pre-determined limit was reached, breaking infinite loops. Salim asked everyone if this should be fixed or if we should just forget about this issue and move on. Miller proposed to keep a one-behind state for the packet, fixing the simplest case (two interfaces). The general case, however, would requite a bitmap of all the interfaces to be scanned, which would impose a large overhead. Miller said an attempt to fix this should somehow be made. The root of the problem is that the network maintainers are trying to reduce the size of the skb structure, because it's used in many critical paths of the network stack. Salim's position is that, without the TTL fields, there is no way to fix the general case here, and this constitutes a security issue. So either the bits need to be brought back, or we need to live with the inherent DoS threat.

Dumping large statistics sets Another issue Salim brought up was the question of how to export large statistics sets from the kernel. It turns out that some use cases may end up dumping a lot of data. Salim mentioned a real-world tc use case that calls for reading six-million entries. The current netlink-based API provides a way to get only 20 entries at a time, which means it takes forever to dump the state of all those policy actions. Salim has a patch that changes the dump size be eight times the NLMSG_GOOD_SIZE, which improves performance by an order of magnitude already, although there are issues with checking the user-space buffer size there. But a more complete solution is needed. What Salim proposed was a way to ask only for the states that changed since the last dump was requested. He has a patch to add a last_access field to the netlink_callback structure used by netlink_dump() to output data; that raised the question of how to actually use that field. Since Salim fetches that data every five seconds, he figured he could just tell the kernel to return all the nodes that changed in that period. But then if the dump takes more than five seconds to complete, the next dump may be missing states that changed during the extra delay. An alternative mechanism would be for the user-space utility to keep the time stamp it requested and use that as a delta for the next dump. It turns out this is a larger problem than just tc. Dumazet mentioned this was an issue with fq_codel classes: he would even like to be able to dump those statistics faster than every five seconds. Roopa Prabhu mentioned that Cumulus also has similar problems dumping stats from bridges, so clearly a more generic solution is needed here. There is, however, a fundamental problem with dumping large statistics sets from the kernel: those statistics are constantly changing while the dump is created and unless versioning or locking mechanisms are used which would slow things down the data returned is bound to be only an approximation of reality. Salim promised to send a set of RFC patches to further discussions regarding this issue, but during the following Netdev conference, Berg published a patch to fix this ten-year-old issue, which brought cheers from the audience.
The author would like to thank the Netconf and Netdev organizers for travel to, and hosting assistance in, Toronto. Many thanks to Berg, Dumazet, Salim, and Sowa for their time taken for a technical review of this article. Note: this article first appeared in the Linux Weekly News.

29 March 2017

Daniel Pocock: Brexit: If it looks like racism, if it smells like racism and if it feels like racism, who else but a politician could argue it isn't?

Since the EU referendum got under way in the UK, it has become almost an everyday occurence to turn on the TV and hear some politician explaining "I don't mean to sound racist, but..." (example) Of course, if you didn't mean to sound racist, you wouldn't sound racist in the first place, now would you? The reality is, whether you like politics or not, political leaders have a significant impact on society and the massive rise in UK hate crimes, including deaths of Polish workers, is a direct reflection of the leadership (or profound lack of it) coming down from Westminster. Maybe you don't mean to sound racist, but if this is the impact your words are having, maybe it's time to shut up? Choosing your referendum Why choose to have a referendum on immigration issues and not on any number of other significant topics? Why not have a referendum on nuking Mr Putin to punish him for what looks like an act of terrorism against the Malaysian Airlines flight MH17? Why not have a referendum on cutting taxes or raising speed limits, turning British motorways into freeways or an autobahn? Why choose to keep those issues in the hands of the Government, but invite the man-in-a-white-van from middle England to regurgitate Nigel Farage's fears and anxieties about migrants onto a ballot paper? Even if David Cameron sincerely hoped and believed that the referendum would turn out otherwise, surely he must have contemplated that he was playing Russian Roulette with the future of millions of innocent people? Let's start at the top For those who are fortunate enough to live in parts of the world where the press provides little exposure to the antics of British royalty, an interesting fact you may have missed is that the Queen's husband, Prince Philip, Duke of Edinburgh is actually a foreigner. He was born in Greece and has Danish and German ancestry. Migration (in both directions) is right at the heart of the UK's identity. Queen and Prince Philip Home office minister Amber Rudd recently suggested British firms should publish details about how many foreign people they employ and in which positions. She argued this is necessary to help boost funding for training local people. If that is such a brilliant idea, why hasn't it worked for the Premier League? It is a matter of public knowledge how many foreigners play football in England's most prestigious division, so why hasn't this caused local clubs to boost training budgets for local recruits? After all, when you consider that England hasn't won a World Cup since 1966, what have they got to lose? Kevin Pietersen All this racism, it's just not cricket. Or is it? One of the most remarkable cricketers to play for England in recent times, Kevin Pietersen, dubbed "the most complete batsman in cricket" by The Times and "England's greatest modern batsman" by the Guardian, was born in South Africa. In the five years he was contracted to the Hampshire county team, he only played one match, because he was too busy representing England abroad. His highest position was nothing less than becoming England's team captain. Are the British superior to every other European citizen? One of the implications of the rhetoric coming out of London these days is that the British are superior to their neighbours, entitled to have their cake and eat it too, making foreigners queue up at Paris' Gare du Nord to board the Eurostar while British travelers should be able to walk or drive into European countries unchallenged. This superiority complex is not uniquely British, you can observe similar delusions are rampant in many of the places where I've lived, including Australia, Switzerland and France. America's Donald Trump has taken this style of politics to a new level. Look in the mirror Theresa May: after British 10-year old schoolboys Robert Thompson and Jon Venables abducted, tortured, murdered and mutilated 2 year old James Bulger in 1993, why not have all British schoolchildren fingerprinted and added to the police DNA database? Why should "security" only apply based on the country where people are born, their religion or skin colour? Jon Venables and Robert Thompson In fact, after Brexit, people like Venables and Thompson will remain in Britain while a Dutch woman, educated at Cambridge and with two British children will not. If that isn't racism, what is? Running foreigner's off the roads Theresa May has only been Prime Minister for less than a year but she has a history of bullying and abusing foreigners in her previous role in the Home Office. One example of this was a policy of removing driving licenses from foreigners, which has caused administrative chaos and even taken away the licenses of many people who technically should not have been subject to these regulations anyway. Shouldn't the DVLA (Britain's office for driving licenses) simply focus on the competence of somebody to drive a vehicle? Bringing all these other factors into licensing creates a hostile environment full of mistakes and inconvenience at best and opportunities for low-level officials to engage in arbitrary acts of racism and discrimination. Of course, when you are taking your country on the road to nowhere, who needs a driving license anyway? Run off the road What does "maximum control" over other human beings mean to you? The new British PM has said she wants "maximum control" over immigrants. What exactly does "maximum control" mean? Donald Trump appears to be promising "maximum control" over Muslims, Hitler sought "maximum control" over the Jews, hasn't the whole point of the EU been to avoid similar situations from ever arising again? This talk of "maximum control" in British politics has grown like a weed out of the UKIP. One of their senior figures has been linked to kidnappings and extortion, which reveals a lot about the character of the people who want to devise and administer these policies. Similar people in Australia aspire to jobs in the immigration department where they can extort money out of people for getting them pushed up the queue. It is no surprise that the first member of Australia's parliament ever sent to jail was put there for obtaining bribes and sexual favours from immigrants. When Nigel Farage talks about copying the Australian immigration system, he is talking about creating jobs like these for his mates. Even if "maximum control" is important, who really believes that a bunch of bullies in Westminster should have the power to exercise that control? Is May saying that British bosses are no longer competent to make their own decisions about who to employ or that British citizens are not reliable enough to make their own decisions about who they marry and they need a helping hand from paper-pushers in the immigration department? maximum control over Jewish people Echoes of the Third Reich Most people associate acts of mass murder with the Germans who lived in the time of Adolf Hitler. These are the stories told over and and over again in movies, books and the press. Look more closely, however, and it appears that the vast majority of Germans were not in immediate contact with the gas chambers. Even Gobels' secretary writes that she was completely oblivious to it all. Many people were simply small cogs in a big bad machine. The clues were there, but many of them couldn't see the big picture. Even if they did get a whiff of it, many chose not to ask questions, to carry on with their comfortable lives. Today, with mass media and the Internet, it is a lot easier for people to discover the truth if they look, but many are still reluctant to do so. Consider, for example, the fingerprint scanners installed in British post offices and police stations to fingerprint foreigners and criminals (as if they have something in common). If all the post office staff refused to engage in racist conduct the fingerprint scanners would be put out of service. Nonetheless, these people carry on, just doing their job, just following orders. It was through many small abuses like this, rather than mass murder on every street corner, that Hitler motivated an entire nation to serve his evil purposes. Technology like this is introduced in small steps: first it was used for serious criminals, then anybody accused of a crime, then people from Africa and next it appears they will try and apply it to all EU citizens remaining in the UK. How will a British man married to a French woman explain to their children that mummy has to be fingerprinted by the border guard each time they return from vacation? The Nazis pioneered biometric technology with the tracking numbers branded onto Jews. While today's technology is electronic and digital, isn't it performing the same function? There is no middle ground between "soft" and "hard" brexit An important point for British citizens and foreigners in the UK to consider today is that there is no compromise between a "soft" Brexit and a "hard" Brexit. It is one or the other. Anything less (for example, a deal that is "better" for British companies and worse for EU citizens) would imply that the British are a superior species and it is impossible to imagine the EU putting their stamp on such a deal. Anybody from the EU who is trying to make a life in the UK now is playing a game of Russian Roulette - sure, everything might be fine if it morphs into "soft" Brexit, but if Theresa May has her way, at some point in your life, maybe 20 years down the track, you could be rounded up by the gestapo and thrown behind bars for a parking violation. There has already been a five-fold increase in the detention of EU citizens in British concentration camps and they are using grandmothers from Asian countries to refine their tactics for the efficient removal of EU citizens. One can only wonder what type of monsters Theresa May has been employing to run such inhumane operations. This is not politics Edmund Burke's quote "The only thing necessary for the triumph of evil is for good men to do nothing" comes to mind on a day like today. Too many people think it is just politics and they can go on with their lives and ignore it. Barely half the British population voted in the referendum. This is about human beings treating each other with dignity and respect. Anything less is abhorrent and may well come back to bite.

27 March 2017

Elena 'valhalla' Grandi: New pajama

New pajama

I may have been sewing myself a new pajama.

Immagine/fotohttp://social.gl-como.it/photos/valhalla/image/81b600789aa02a91fdf62f54a71b1ba0

It was plagued with issues; one of the sleeve is wrong side out and I only realized it when everything was almost done (luckily the pattern is symmetric and it is barely noticeable) and the swirl moved while I was sewing it on (and the sewing machine got stuck multiple times: next time I'm using interfacing, full stop.), and it's a bit deformed, but it's done.

For the swirl, I used Inkscape to Simplify (Ctrl-L) the original Debian Swirl a few times, removed the isolated bits, adjusted some spline nodes by hand and printed on paper. I've then cut, used water soluble glue to attach it to the wrong side of a scrap of red fabric, cut the fabric, removed the paper and then pinned and sewed the fabric on the pajama top.
As mentioned above, the next time I'm doing something like this, some interfacing will be involved somewhere, to keep me sane and the sewing machine happy.

Blogging, because it is somewhat relevant to Free Software :) and there are even sources https://www.trueelena.org/clothing/projects/pajamas_set.html#downloads, under a DFSG-Free license :)

24 March 2017

Gunnar Wolf: Dear lazyweb: How would you visualize..?

Dear lazyweb, I am trying to get a good way to present the categorization of several cases studied with a fitting graph. I am rating several vulnerabilities / failures according to James Cebula et. al.'s paper, A taxonomy of Operational Cyber Security Risks; this is a somewhat deep taxonomy, with 57 end items, but organized in a three levels deep hierarchy. Copying a table from the cited paper (click to display it full-sized): My categorization is binary: I care only whether it falls within a given category or not. My first stab at this was to represent each case using a star or radar graph. As an example: As you can see, to a "bare" star graph, I added a background color for each top-level category (blue for actions of people, green for systems and technology failures), red for failed internal processes and gray for external events), and printed out only the labels for the second level categories; for an accurate reading of the graphs, you have to refer to the table and count bars. And, yes, according to the Engineering Statistics Handbook:
Star plots are helpful for small-to-moderate-sized multivariate data sets. Their primary weakness is that their effectiveness is limited to data sets with less than a few hundred points. After that, they tend to be overwhelming.
I strongly agree with the above statement And stating that "a few hundred points" can be understood is even an overstatement. 50 points are just too much. Now, trying to increase usability for this graph, I came across the Sunburst diagram. One of the proponents for this diagram, John Stasko, has written quite a bit about it. Now... How to create my beautiful Sunburst diagram? That's a tougher one. Even though the page I linked to in the (great!) Data visualization catalogue presents even some free-as-in-software tools to do this... They are Javascript projects that will render their beautiful plots (even including an animation)... To the browser. I need them for a static (i.e. to be printed) document. Yes, I can screenshot and all, but I want them to be automatically generated, so I can review and regenerate them all automatically. Oh, I could just write JSON and use SaaS sites such as Aculocity to do the heavy-lifting, but if you know me, you will understand why I don't want to. So... I set out to find a Gunnar-approved way to display the information I need. Now, as the Protovis documentation says, an icicle is simply a sunburst transformed from polar to cartesian coordinates... But I came to a similar conclusion: The tools I found are not what I need. OK, but an icicle graph seems much simpler to produce I fired up my Emacs, and started writing using Ruby, RMagick and RVG... I decided to try a different way. This is my result so far: So... What do you think? Does this look right to you? Clearer than the previous one? Worst? Do you have any idea on how I could make this better? Oh... You want to tell me there is something odd about it? Well, yes, of course! I still need to tweak it quite a bit. Would you believe me if I told you this is not really a left-to-right icicle graph, but rather a strangely formatted Graphviz non-directed graph using the dot formatter? I can assure you you don't want to look at my Graphviz sources... But in case you insist... Take them and laugh. Or cry. Of course, this file comes from a hand-crafted template, but has some autogenerated bits to it. I have still to tweak it quite a bit to correct several of its usability shortcomings, but at least it looks somewhat like what I want to achieve. Anyway, I started out by making a "dear lazyweb" question. So, here it goes: Do you think I'm using the right visualization for my data? Do you have any better suggestions, either of a graph or of a graph-generating tool? Thanks! [update] Thanks for the first pointer, Lazyweb! I found a beautiful solution; we will see if it is what I need or not (it is too space-greedy to be readable... But I will check it out more thoroughly). It lays out much better than anything I can spew out by myself Writing it as a mindmap using TikZ directly from within LaTeX, I get the following result:

19 March 2017

Dirk Eddelbuettel: Rcpp 0.12.10: Some small fixes

The tenth update in the 0.12.* series of Rcpp just made it to the main CRAN repository providing GNU R with by now over 10,000 packages. Windows binaries for Rcpp, as well as updated Debian packages will follow in due course. This 0.12.10 release follows the 0.12.0 release from late July, the 0.12.1 release in September, the 0.12.2 release in November, the 0.12.3 release in January, the 0.12.4 release in March, the 0.12.5 release in May, the 0.12.6 release in July, the 0.12.7 release in September, the 0.12.8 release in November, and the 0.12.9 release in January --- making it the fourteenth release at the steady and predictable bi-montly release frequency. Rcpp has become the most popular way of enhancing GNU R with C or C++ code. As of today, 975 packages on CRAN depend on Rcpp for making analytical code go faster and further. That is up by sixtynine packages over the two months since the last release -- or just over a package a day! The changes in this release are almost exclusively minor bugfixes and enhancements to documentation and features: James "coatless" Balamuta rounded out the API, I aki Ucar fixed a bug concerning one-character output, Jeroen Ooms allowed for finalizers on XPtr objects, Nathan Russell corrected handling of lower (upper) triangular matrices, Dan Dillon and I dealt with Intel compiler quirks for his algorithm.h header, and I added a C++17 plugin along with some (overdue!) documentation regarding the various C++ standards that are supported by Rcpp (which is in essence whatever your compiler supports, i.e., C++98, C++11, C++14 all the way to C++17 but always keep in mind what CRAN and different users may deploy).

Changes in Rcpp version 0.12.10 (2017-03-17)
  • Changes in Rcpp API:
    • Added new size attribute aliases for number of rows and columns in DataFrame (James Balamuta in #638 addressing #630).
    • Fixed single-character handling in Rstreambuf (I aki Ucar in #649 addressing #647).
    • XPtr gains a parameter finalizeOnExit to enable running the finalizer when R quits (Jeroen Ooms in #656 addressing #655).
  • Changes in Rcpp Sugar:
    • Fixed sugar functions upper_tri() and lower_tri() (Nathan Russell in #642 addressing #641).
    • The algorithm.h file now accomodates the Intel compiler (Dirk in #643 and Dan in #645 addressing issue #640).
  • Changes in Rcpp Attributes
    • The C++17 standard is supported with a new plugin (used eg for g++-6.2).
  • Changes in Rcpp Documentation:
    • An overdue explanation of how C++11, C++14, and C++17 can be used was added to the Rcpp FAQ.

Thanks to CRANberries, you can also look at a diff to the previous release. As always, even fuller details are on the Rcpp Changelog page and the Rcpp page which also leads to the downloads page, the browseable doxygen docs and zip files of doxygen output for the standard formats. A local directory has source and documentation too. Questions, comments etc should go to the rcpp-devel mailing list off the R-Forge page.

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

14 March 2017

Reproducible builds folks: Reproducible Builds: week 98 in Stretch cycle

Here's what happened in the Reproducible Builds effort between Sunday March 5 and Saturday March 11 2017: Upcoming events Reproducible Builds Hackathon Hamburg The Reproducible Builds Hamburg Hackathon 2017, or RB-HH-2017 for short, is a 3 day hacking event taking place in the CCC Hamburg Hackerspace located inside the Frappant, which is collective art space located in a historical monument in Hamburg, Germany. The aim of the hackathon is to spent some days working on Reproducible Builds in every distribution and project. The event is open to anybody interested on working on Reproducible Builds issues in any distro or project, with or without prio experience! Packages filed Chris Lamb: Toolchain development Reviews of unreproducible packages 39 package reviews have been added, 7 have been updated and 9 have been removed in this week, adding to our knowledge about identified issues. 2 issue types have been added: Weekly QA work During our reproducibility testing, FTBFS bugs have been detected and reported by: buildinfo.debian.net development reproducible-website development tests.reproducible-builds.org Misc. This week's edition was written by Chris Lamb, Holger Levsen, Vagrant Cascadian & reviewed by a bunch of Reproducible Builds folks on IRC & the mailing lists.

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