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Diary, May 2024


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Wednesday, May 1, 2024

Book fair Glanerbrug

This morning, I went to the book fair in Glanerbrug. I first donated some books from my own collection: I primarily searched the art book shelves. There were less interesting books than last year. Still, at 11:51, I bought the following books:

27.3° Celsius

The temperature at Twenthe Airport has gone up to 27.3° Celsius, which breaks the previous record of 26.5° on this date in 2005. Last Satuday, the Daily Sea Surface Temperature for North Atlantic (0-60°N, 0-80°W) dropped below last years record high breaking a period of 420 days of daily record temperatures. For the World (60°S-60°N, 0-360°E) there has been a record since March 14, 2024 and there is still no sign of it dropping below the previous record.

Friday, May 3, 2024

Exhibitions at University of Twnete

When I studied at University of Twente (then still called Technische Hogeschool Twente), I once saw an artwork in the Vrijfhof-building that consisted of a number of books where on every page that were stamped but a single letter. If I recall correctly the letters formed the text of the Dutch translation of Ecclesiastes. I have tried before to find out who made this art work. There is no mention of it in my diaries. (In that time, I used not to write about what I did or saw.) Yesterday, I spend some time to go through all the university newspapers of the periode 1982 till 1986 to find out of I could find something more. Today, I spend some time to find links for these exhibitions. I get the idea that not all exhbitions are mentioned in the unversity newspaper. I do remember having seen several exhibitions with wooden mechanical devices including music instruments. Below the list of exhibitions I found.

Sunday, May 5, 2024

GNU Mes

In the past week, I have been working on getting the i386 Eumlator to execute the GNU Mes compiler. For that I only had to implement some additional instructions and also a number of system calls, some of which I wonder why they are needed. The Mes compiler executes rather slow in the emulator. One reaons is that it uses a Scheme interpreter to implement the compiler. So, it is running an interpreter within an interpreter (because the emulator is basically an interpreter executing machine code). It looks like the parse is table written. If so, this can be seen as another interpreter. The GNU Mes is an odd one out in the whole chain, because it is implemented in a subset of C, implementing a C compiler to compile (several versions of) the Tiny C Compiler, which again is used to compiler a version of the GNU C compiler. Why bridge the 'gap' between the subset of C compiler and what is needed to compile the Tiny C Compiler. It seems to me that the gap is not that big, also because (I expect) that not all C is used in the implementation of Tiny C compiler.

Books

This afternoon, I again visited the book fair in Glanerbrug. It was the last day and they had a 50% discount. I primarily searched the art book shelves. At about 13:08, I bought the following books:

After this I bike to the Maker Festival organized by TETEM art space. Inside TETEM, I watched the Narcissus art work and the self-build plotter by Roland Blok. The plotter is used for Single Line Selfie, which makes use of software he developed himself. I also watched the exhibition Kindness Practice by Handi Kim. Outside, I saw the Linuparus meridionalis animaltonics build by Tristan Kruithof and heard the 'Robot Max', a drum robot, by Ponytrap. I met someone who I knew whoe remarked that the age category of the goal audience is getting lower and lower each year. I could not deny his statement.

I went to bookshop Broekhuis and at 14:38:14, I bought the following three books for € 10.00 from the outside sale:

Monday, May 6, 2024

Hytti nro 6

Yesterday evening (and early this night), we watched the film Hytti nro 6 (in English called Compartment No.6) from 2021 on TV, in which a Finnish girl called Laura travels from Moscow to Murmansk because she wants to see the petroglyps at some islands on Lake Kanozero. Most of them are located on the Kamenny island. When she arrives in Murmansk she hears that in the winter it is not possible to see the petroglyps, but with the help of some people she finally succeeds to visit the island (but it is not clear if she found the petroglyps). According to Google Maps it is about 5 hour drive to get to the lake. If she would had get out of the train at Apatity it would have been a little more than 2 hour drive. The film is loosly based on a novel with the same title from 2011 with the same title by Rosa Liksom.

Arabic Typography

I have started reading the book Arabic Typography: History and Practice with Titus Nemeth as editor and author. On page 8 in footnote 18 it says: 'A related observation can be made for the exchange on theoretical matters between Donald Knuth and Douglas Hofstadter in Visible Language (XVI, 4, 1982), which appears to take place in an idealized context with a single writing system, and - especially from Knuth's point of view - little acknowledgement of the cultural load of letterforms.' This seems to refer to articles The Concept of a Meta-Font by Donald Knuth and Metafont, Metamathematics, and Metaphysics: Comments on Donald Knuth's Article “The Concept of a Meta-Font” by Douglas Hofstadter. Metafont played in important role in the early history of computer fonts. The first fonts used in computers where bitmaps. The first vector based fonts were developed before Metafont in 1974. Metafont came around the same time as the development of PostScript, which started around 1976 and released to the market in 1984, and PostScript fonts. which later lead to the development of other vector based font systems such as OpenType and TrueType.

On page 12, it mentions that at the start of the seventeen century, the center of Arabic printing and Arabic studies moved from Italy to the Netherlands and that Thomas Erpenius played an important role. He published the book Grammatica Arabica written in Latin, which presents a grammar for Arabic. The grammar starts on page 203 (of a total of 846 pages) with the chapter Orthographia. In the following pages, I often see the use of kashida. It seems it is not always used for justification, but also to make it easier to identify the separate letters beter for readers not very familiar with the script.

GNU Mes in emulator

It looks like there might be something wrong with the execution of GNU Mes in the i386 emulator. The execution of the following command (step 227) seems to work: 
./bin/mes-m2 -c "(display 'Hello,M2-mes!) (newline)"
And also the command (step 232): 
/usr/bin/mes-m2 -L module gen-cpp-files.scm
Runs to completion and produces the files: cpp-act.scm and cpp-tab.scm in the directory /steps/mes-0.26/build/nyacc-1.00.2/module/nyacc/lang/c99/mach.d/. But then the execution of the command: 
/usr/bin/mes-m2 -L module gen-c99-files.scm
Seems to get stuck or at least take many hours to complete. I noticed that there might be something wrong with the implemenation of the ioctl system call. I fixed that problem and started the program again. I still is taking a long time to complete the given step.

Debugging an emulator that is running an interpreter is going to be very complicated. I am considering the option to compare my implementation with some other emulators. One example being the x86 emulation library. Or study the QEMU sources in the target/i386/hvf directory.

Saturday, May 11, 2024

Harvest

Today we were able to pick up the first new harvest of this year at Herenboeren Usseler Es and we ate some of it yesterday. Below is a photo of the harvest. At the front are the herbs (from left to right): dill, plantain, parsley and coriander. Behind this are the vegetables (clockwise, starting at the bottom left): arugula, spinach, head of lettuce (own variety), flowering bok choy and another head of lettuce.

Aurora borealis

Last night I went outside several times to look in our backyard to see if I could see any of the aurora borealis caused by the solar storms. There was some light polution due to some cloud cover. I was not in the mood to bike to a darker spot about 5 minutes away, afraid that it would be for nothing. I did noticed some pink glow and went to get my camera and a tripot, but it the glow seemed gone when I took some pictures. Today, I downloaded the pictures, which turned out very dark. I fiddled a bit with the brightness and the constrast, resulting in the image shown below, which does clearly show a pink glow. Others have made much beter pictures, also from my neighborhood, which I saw on social media.

Sunday, May 12, 2024

Ten books with unique concepts

I watched the video 10 books with unique concepts (that will blow your mind) by Nicholas Beutler. In the comments it lists the ten books with only links to Amazon. These are the books that are mentioned with some more informative links:

Using strace

I continued with my research of live-bootstrap by using strace command. I wrote the following bash script, which expect a clone of live-bootstrap in a sibling directory in which the download-distfiles.sh script has been executed as well: 

#! /bin/bash
rm -rf rootfs
mkdir rootfs
cd rootfs
cp -r -t . ../../live-bootstrap/seed/stage0-posix/*
cp -rf -t . ../../live-bootstrap/seed/*.kaem
cp -r -t . ../../live-bootstrap/seed/*.checksums
cp -r -t . ../../live-bootstrap/seed/*.c
cp -r -t . ../../live-bootstrap/steps
mkdir external
cp -r -t external ../../live-bootstrap/distfiles
cp ../replacement/steps/bootstrap.cfg steps
cd ..
strace -f -o trace.txt -e \
  trace=open,openat,close,chmod,chdir,dup,fcntl,link,linkat,unlink,fork,execve \
  chroot rootfs /bootstrap-seeds/POSIX/x86/kaem-optional-seed

I terminated the execution at some point at which the file trace.txt reached a size of 1.1Gbyte and reported 622,379 calls of execve system calls, which represent an execution of a program. I the next step will be to write a program to analyze (part of) this file.

Friday, May 17, 2024

De Waarbeek

I biked to De Waarbeek, a small amusement park, where I met with Andy and others from his residential care group. This was organized by an organization that organizes events for people with an intellectual disability. Andy was looking around who were all there and met some people he knew from the past. He also approached a Chinese looking young women. She did not know him and I explained that his mother was Chinese. One of the first rides he was took was the 'ducks' ride. He remembered that he took it in 2005. See this picture. Below the photo, I took of him while on the ride:

While at the park, I also read the exhibition catalog CODA Paper Art from 2007 while standing in several queues for the rides. At one point I pondered how the world of people with an intellectual disability is separate world. I also thought about how our world is thus thin organic layer on our planet when viewed on a planitary scale. At two o'clock we attended a theater show with some singing and magic tricks. About three o'clock, Andy went home with the others and I went to visit Bert and Cornelise (who live about ten minuted biking away) and stayed with them for a bit less than two hours before going home.

Saturday, May 18, 2024

Lakenvelder cattle

Today there was some harvest at Herenboeren Usseler Es to be collected and there was an opportunity to meet with the five Lakenvelder cattle that arrived last week. Below is a photo of the harvest. On the left front a mixture of mesclun and mustard leaves, on the back radishes with leaves and on the right front some spinach. The foliage of the radish is edible and even healthy. We may combine it with the spinach.

Processing strace output

In the past week, I worked on a program to parse the output produced by the strace command when executing live-bootstrap. It is kind of similar to what I did last year before and can be viewed here. The new result can be found here. For Process 731 that produces tcc-boot0 it also shows all the sources that are being used directly and indirectly. In case sources that are unpacked with the untar program from a source distribution and are executed they are listed is binary seeds. That does not happen for as far as the program parses the output.

Sunday, May 19, 2024

KunstenLandschap 2024

I biked around the route of KunstenLandschap 2024. This year, you received a separate map for the route. Before the route would be in the booklet. The size of the booklet is also a bit smaller. I bought my ticket at Rijksmuseum Twente. I quickly walked through the exhibitions The international landscape. Painting in the open air in the nineteenth century (which we already visited) and Kees Stoop. Below the list of locations part of KunstenLandschap in the order I visited them. The locations indicated with a letter belong to the permanent KunstenLanschap route. by:

Monday, May 20, 2024

Exhibitions

At Concordia I saw two exhibitions. The first is called Het Paviljoen #3 with the following works by students of the AKI: The second exhibition is called Verborgen leven/Hidden life with works by artist from De Kunsthaven. I liked the works by the following artists: Next I went back to two places related to KunstenLanschap. At location 15, I saw: I also bought a vine tomato plant for € 2.50, which I planted in the back garden after I arrived at home. Finally, I went to location 4 to see the performance An die Ungehörten (To Those Unheard) by Mikes Poppe again.

Thursday, May 23, 2024

Rainbow

On the 8 o'clock news there was an item on slugs because there are so many this year due to the wet weather in the past months, the lack of freezing during the winter and the reduction of natural enemies. I went outside to check the tomato plant we planted last Monday. I saw it was still doing well. When I walked back, I saw a rainbow, an almost complete rainbow and partial (on the left) double rainbow. I went inside to get my camara and when I wanted to take a picture, I noticed some kind of wire in the top right corner of the screen. Cleaning the lens did not help. My idea was that it must be inside the camera. When I took a picture, it became out of focus, but in the pictures it was still visible if you knew what to look for. The picture shown below, which is a section of the picture, there is a darker spot visible near the top right corner. After having taken two pictures and watch the rainbow some more, I went inside and opened up my Panasonic Lumix DMC-TZ8 (like I did before on February 21, 2018) and removed a very small, wire like piece of dirt from the window before the sensor. For this I had to remove the sensor, something that I had not done before. After I had put everything together again, the camera seemed to be working as normal.

Saturday, May 25, 2024

Harvest

Today, the harvest of Herenboeren Usseler Es consisted of (for us): two heads of endive, spinach sprouts, coriander and sage. When I washed the heads of endive, I found on small snail and two small slugs. I used the coriander in the soto (a traditional Indonesian soup) that Conny had prepared.

Opening of Ctrl.Bending

In the evening, I went to the opening of the exhibition Ctrl.Bending at Concordia, which was organised in cooperation with Sickhouse. The exhibition is part of Sickhouse's year research "Radical-Joy-Resistance" leading to The Overkill festival. The following works/games are part of the exhibition:

At 20:30, Manu Louis gave a performance/concert. I found it quite interesting, but I went outside because I found the sound a bit too loud.

Addition May 20: Post on Instagram.

Monday, May 27, 2024

Geolocating a photo

In some facebook group a photo posted that was taken from this tweet. I immediately guessed that it was taken along the Amsterdam–Rhine Canal. Some people in that group concluded that it must have been photoshopped. At first I thought it was taken from the west side of the canal looking north (towards Amsterdam), but later I discovered that it was taken from the east side of the canal looking south (towards Utrecht). I spend some time looking in streetview for the exact location where it was taken and I think I found a good match. Notice that the first tree on the left of which the trunk is completely in the picture has an off branch on the right side that goes almost vertical. All other trees have branches going up. Also the fencing behind the tree matches. A little further on this road the fencing is gone. In this area of the country most fields as separated by ditches such that no fences are needed.

Addition May 29: When your Photograph Goes Viral.

Wednesday, May 29, 2024

Parsing Tiny C Compiler sources

In the past weeks, I worked on parsing the sources of the Tiny C Compiler as part of an investigation to replace the Gnu MES Compiler that is used in live-bootstrap. I first wrote a minimal C preprocessor: min_tcc_preprocessor.cpp. The output file (which does not include the required standard include files) has 23.487 lines and contains more than half a megabyte characters. Not what you expect with something that is called tiny. Next, I worked on RawParser to complete the C-grammar parsing, fixing some bugs and adding some additional checks, such that it could parse the output of the preprocessor program. The different uses of the sizeof operator posed some problems. I personally only use the sizeof operator with a type and never with an expression. The parsing does not result in a complete abstract syntax tree, as far as I know. So, this is just the first step and there is more work to do.

This months interesting links

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