Notes about Computers, Computing, Computations, Etc.

1. AltDrag lets Windows 10 have Linux-style “hold down a key and click to move a window” support. 1.48Download
2. Divvy divides up your screen and lets you move windows to different sections with keyboard shortcuts. Download

stable diffusion notes

Some notes about Ionic.

Notes about Qt

Notes about Yocto

Manipulating Dokuwiki Dates the Hard Way

Publii

Clean up a variety of caches on Windows

Change video container from Matroska (mkv) to mp4 (assuming the video codec is supported by mp4):

ffmpeg -i name_of_input_file.mkv -codec copy output_file.mp4
# If there's issues with the audio codec:
ffmpeg -i name_of_input_file.mkv -c:v copy -c:a aac output_file.mp4

Download a Youtube playlist, keeping only the audio in AAC (.m4a) format:

yt-dlp -f 140 -o "%(playlist)s/%(playlist_index)s - %(title)s.%(ext)s" "https://www.youtube.com/playlist?list=PLaro_mvk6VEkTqkmTcUIvr4MnUzfh434-"

Download a Youtube video in a h264 video and AAC audio:

yt-dlp -f 22+140 https://www.youtube.com/watch?v=cnDJa_HZVP0

To fix photo dates when people email you photos and you need to import them into your photo manager and your photo manager shows all the photos as taken today even though you know they were taken weeks ago but people are so bad at sending photos….

# Inspect the original timestamp
exiftool -r -DateTimeOriginal path_to_picture_folder
# Inspect the modification timestamp
exiftool -r -FileModifyDate path_to_picture_folder
# If FileModifyDate doesn't match what you need, you can set it to the original timestamp
# Note: The double quotes are important so that the shell doesn't think you're redirecting I/O from a file.
exiftool -r "-FileModifyDate<DateTimeOriginal" path_to_picture_folder

Windows lock screen backgrounds don't support tiling so I use ImageMagick to create a large image made of my tiles:

convert -size 2560x1080 tile:image_to_tile.png tiled_img.jpg

moved to its own section

EndeavourOS Setup

sudo apt install ubuntu-drivers-common
sudo ubuntu-drivers list --gpgpu
sudo ubuntu-drivers install --gpgpu

Condensed from this ServerFault post:

# Make group for no-net access, add user to group
groupadd no-net
usermod -a -G no-net USERNAME
groups USERNAME
# Rules to allow local network access
iptables -A OUTPUT -m owner --gid-owner no-net -d 192.168.1.0/24 -j ACCEPT
iptables -A OUTPUT -m owner --gid-owner no-net -d 127.0.0.0/8 -j ACCEPT
# Rule to block other network access
iptables -A OUTPUT -m owner --gid-owner no-net -j DROP
# Rule to block outbound IPv6
ip6tables -A OUTPUT -m owner --gid-owner no-net -j DROP
# Create a script called ''no-net'' containing the following two lines:
#!/bin/bash
sg no-net "$@"

There are a couple ways to install Xfce, I prefer the first option:

1. apt install xubuntu-core - perfect; includes whisker-menu for a good application launcher.
2. apt install –no-install-recommends xubuntu-core - boots to GUI, very barebones (not even xfce4-terminal).
3. apt install xfce4 - gives basic installation, still boots to console, so start GUI with startx.

Don't bother with apt install xfce4 –no-install-recommends because apparently installing xorg is just a recommendation, so startx/startxfce will fail :D

# Get rid of cloud init
apt purge -y cloud-init
# Disable IPv6 in the kernel by modifying the CMDLINE options in /etc/default/grub:
GRUB_CMDLINE_LINUX_DEFAULT="ipv6.disable=1"
GRUB_CMDLINE_LINUX="ipv6.disable=1"
update-grub
# Edit /etc/default/keyboard to include:
XKBOPTIONS="ctrl:nocaps"

sudo apt install linux-generic-hwe-22.04

Guide to getting Synology ActiveBackup running on Ubuntu 20.04

Settings for a good-looking Xfce4 installation:

• Style: Greybird
• Icons: Elementary Xfce dark
• Window Theme: Arc-dark

On Debian these are installed with: sudo apt install greybird-gtk-theme elementary-xfce-icon-theme arc-theme

Here are some extensive notes on setting this up. I also have a version for CentOS 8 (RIP) but don't maintain/update it.

Notes on setting up Kanboard on Ubuntu.

Sometimes you have to make a program start automatically at boot. Here's how I do it with systemd.

This came up because I was messing with partition layouts for a project and Xfce kept automatically mounting the drives while I was working on them.

# Don't automount drives
xfconf-query -c thunar-volman -p /automount-drives/enabled -s false
# Don't automount media (CDs?)
xfconf-query -c thunar-volman -p /automount-media/enabled -s false

# backup
dd bs=4M if=/dev/mmcblk0 | gzip > /mnt/recovery-usb/backupbot-20210715.img.gz
# restore
gunzip --stdout backupbot-20210715.img.gz | sudo dd bs=4M of=/dev/{whatever the device is}

Add a user: createuser someusername -P

Create a database: CREATE DATABASE somedb OWNER someusername TEMPLATE template0 ENCODING 'UTF8';

GRANT CREATE ON SCHEMA public TO username;

/usr/share/doc/postgresql-common/README.md

# In particular, an LRC lyric file.
sed '1 s/^/\n/' */*.lrc -i

Or realize you made a mistake and don't want newlines at the start of every file.

sed -z -i 's/^\n//' */*.lrc

LC_ALL=C find . -name '*[! -~]*'

From https://www.yiiframework.com/wiki/570/remove-byte-order-mark-bom-from-files-recursively

# Make a list of the files
grep -rl $'\xEF\xBB\xBF' .  | grep .lrc > file_with_boms.txt
# Remove the BOM
while read l; do sed -i '1 s/^\xef\xbb\xbf//'  "$l"; done < file_with_boms.txt