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An article by Krister Walfridsson on C pointers are not hardware pointers demonstrated that even adjacent integer variables having the same hardware address may compare unequal regarding C pointers. See the following C program: #include <stdio.h> int main(int argc, char *argv[]) { …
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When analyzing longer text, especially if this text was written by oneself, it helps to read the text in a different way, here using a concordance. Assume your text is provided as PDF. Convert PDF to text using pdftotext, which is part of package poppler. Replace line breaks in text file with…
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The discussion forum for Hugo contains a description: Hugo development - how to contribute code. Also see Contributing to Hugo. 1. Preparation First set GOPATH as export GOPATH=$HOME/tmp/H then cd $GOPATH Fetch source with go get time go get -u -v github.com/spf13/hugo takes around 1-2 minutes…
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HP (Hewlett Packard) manufacturer of printers of various sorts (laser, ink) unfortunately again decided to annoy its loyal customers. Repeatedly HP updated firmware in printers so that they do not work with alternate ink, see for example Disabling 3rd-party ink ensures “best printing…
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In German known as Fünf-Punkte-Satz. This theorem is astounding. It says: If two meromorphic functions share five values ignoring multiplicity, then both functions are equal. Two functions, $f(z)$ and $g(z)$, are said to share the value $a$ if $f(z) - a = 0$ and $g(z) - a = 0$ have the same…
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Recently I had trouble opening PDF documents embedded in Microsoft Word. I speculated about the following reasons for this problem: Adobe Acrobat not installed, I use MuPDF Embedded document simply not "really" embedded but just an icon There is an easy solution. Microsoft Word 2007…
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This blog was viewed more than 50.000 times and had more than 37.000 visitors. I wrote about the development of this blog as follows: 2014/05/07: 5.000 Views 2014/09/10: 10.000 Views 2014/12/27: 15.000 Views 2015/04/23: 20.000 Views 2016/01/24: 30.000 Views 2016/11/12: 40.000 Views The averages…
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As noted in Youtube 500 Internal Server Error today I again noted an "500 Internal Server Error". Normally you would not expect these kind of errors from Google. It says: Sorry, something went wrong. A team of highly trained monkeys has been dispatched to deal with this situation. If you…
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I have written on the Hugo static site generator here. Now I have written a migration program in the Go programming language to convert from WordPress export format to Hugo format. This program wp2hugo.go is in GitHub. It can be freely downloaded and does not need any further dependencies, except,…
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In June 2016 Gustavo Duarte launched Grokbit (dead link). This allows to very easily browse the Linux kernel source tree. This is much better than using Perl, find, grep, etc. for wandering through the code. Added 01-May-2020: Link is dead, so no more grokbit.
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I purchased an Odroid-XU4 for ca. 80 EUR including power-supply and case from Pollin. The original manufacturer is hardkernel. I intended to use this small ARM computer as a router and firewall. In the past I had used routers from multiple vendors, e.g., Linksys/Cisco, TP-Link, AVM/FritzBox,…
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As described in Commuting to Work with an E-Bike I drive to my work place using an e-bike. As I found out that using a bike is a viable alternative to public transport, I bought a better e-bike after about a year. I bought my first e-bike in March 2015, my second in December 2015, and used it since…
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How fast can you wipe a complete disk? For this I dumped zeros to a MS Windows partition based on an SSD formatted with NTFS. [root@i7 ~]# time dd if=/dev/zero of=/dev/sda1 bs=1M dd: error writing '/dev/sda1': No space left on device 81920+0 records in 81919+0 records out 85898297344 bytes (86 GB,…
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In various forums one reads that one should use dd to copy a ISO image to an USB stick. Although this works, more often you do not want to use a ISO image but rather copy a Linux system at hand. First you mount the root filesystem of the new USB stick, then mount /boot within a chroot. Finally use…
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Hearing all these wonder stories about btrfs I decided to give btrfs a try. Additionally I encrypted my SSD using LUKS. The relevant entries in the Arch WIKI are: Setting up LUKS and btrfs. Here is the list of commands I used. 1. I saved my data from SSD using tar and saved tar-file on…
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Just upgraded PulseAudio from 9.0-1 => 10.0-2, which was no good, as I was left with no sound. The bash script downgrade.sh given in Github by Gordian Edenhofer saved the day. Sound is back. The script is for Arch Linux. Usage: downgrade.sh libpulse pulseaudio pulseaudio-bluetooth From now on I…
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A very fine introduction by Prof. Dr. Victoria Kaspi to neutron stars, pulsars, magnetars, binary pulsars. Explaining their use in test for general relativity, and detection of gravitational waves. She also mentions Einstein@Home. Homepage of Prof. Kaspi is here. A recent (6-Jan-2017) observation…
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On 16-Dec-2016 my father died after a long and suffering disease. Born on 28-Nov-1934, he witnessed World-War-II, 1939-1945, separation of Germany, Suez Crisis, 1956, Cuban Missile Crisis, 1962, Vietnam War, Chinese Cultural Revolution, 1966-1976, but also the German reunification, and the Euro. As…
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Cablesurf is a German internet-cable-provider. They deliver Technicolor modem and set-top boxes to the end customers. My cable modem model is: HW Revision 1.0 VENDOR Technicolor BOOT Revision 2.4.0 SW Revision STDD.01.05 MODEL TC7200.20 …
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I wrote on SLURM used on Ubuntu here. As I moved to Arch Linux I, of course, use the fine AUR package slurm-llnl, which was previously maintained by Gordian Edenhofer. After upgrading to version 16.05.7-1 I noticed the following: If slurmd is started by systemd then the pid-file specified for…