Snarf YouTube videos off

Sunday, Mar 21, 2021 is a very cool virtual conference platform. You pick an avatar, can voice chat, video chat, and watch presentations all while standing around in a virtual 2D space. A conference which I attended recently had all the talks pre-recorded and played back at live-time. This worked very well because the presenters would take their time and provide the best possible content. Within the virtual conference space, there was a way to play the videos back through moving your avatar into a specific location that is different for each video.

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Some tips when copying, recovering disks

Sunday, Mar 14, 2021

I seem to have a lot of suggestions to share with friends about managing disks on a linux livecd. Here are some of the tips I’d like to share. See the table of contents above for a breakdown of the topics discussed. Some disk related topics are out of scope for this article, as they deserve their own blog post. The topics not covered include partitioning, setting up a boot loader, using LVM2 or ZFS, that sort of thing.

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You want sudo -i or su -

Sunday, Feb 14, 2021

You want to use sudo -i or su - to log into root. sudo su anything is superfluous, because you probably should be using sudo -i or sudo -s, which are roughly equivalent, depending if you want to simulate a login (su - or sudo -i) or not (su or sudo -s).1 When to use su -? You want to log into root using the root password. Typically you must be in the wheel group (check your PAM configuration).

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About my keyboard choices

Tuesday, Nov 3, 2020

Disclaimer: Dvorak, fancy keyboards, whatever, does not replace good lifestyle habits such as computer breaks, good desk ergonomics, and balancing one’s computer life with gasp real life. Dvorak and fancy keyboards can make your life better, but they cannot completely address RSI problems alone. Since sometime 2013 I have faced pain, numbness, and tightness in my hands due to computer overuse. At first I chose to ignore it, but it got so bad I’d take days if not weeks off from prolonged computer use.

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When NAT Bites — Use a Reverse VPN

Monday, Aug 31, 2020

Sometimes I find myself setting up servers on networks with less than ideal network configuration. Most home internets use dynamic IP addresses, which requires extra work to ensure I know the IP address to use when logging into the network from the internet. Another concern is how unreliable home networking gear can be, especially with users tweaking settings without fully appreciating what they’re doing. As a result, I’ve devised an alternate solution to ensure I can always log into boxes hosted on home internet connections.

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Linux dmesg –follow (-w) not working?

Thursday, Apr 30, 2020

For a couple months now, I have noticed that running dmesg -w on my workstation does not appear to print out new kernel messages. In other words dmesg --follow “hangs”. Additionally when running tail -f /var/log/kern.log to monitor new dmesg messages picked up by sysklogd (part of syslogng), the latest messages do not come through until sysklogd periodically “reopens” the /dev/kmsg kernel message buffer. Why is this a problem? This is a problem because I use the dmesg log to monitor important hardware related messages such as the kernel recognizing a USB device or diagnosing bluetooth/wifi issues.

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Debugging Zathura, GTK (don't forget about seccomp)

Friday, Apr 24, 2020

Zathura]] is a fantastic PDF viewer. It also supports Postscript, DjVu, and Comicbook archive. In particular it supports using mupdf for the backend, so it’s rather fast (unlike poppler, used by evince and friends). Here is a screenshot of Zathura: Figure 1: screenshot of zathura Now that I’ve introduced Zathura. I want to talk about a problem I had recently. I wanted to print a document a couple weeks ago, but found whenever I issued a :print command in Zathura, the program would crash.

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