howto/how_to

Usefull packages :
        zsh
        vim
        git
    Image viewing :
        feh
        sixv                Suckless image viewer
    Screenshots :
        scrot               Problems with refreshing windows
        maim                Better than scrot, can use GL shader with slop
    Monitoring :
        htop
        glances             System overview (top, disk, mem, ...)
        ncdu                Disk usage
    Terminal :
        kitty               GPU accelerated term, nicely configurable
        st                  Simple Terminal, very light
        fbterm              Framebuffer terminal, doesn't need X, unmaintained
    Desktop environment :
        dwm                 Dynamic Window Manager
        dmenu
        sway
    Office :
        sent                Simple slides tool
    Misc :
        eg                  Examples of common tools usage (think find or tar)
    Obscure/Useful vim plugins:
        better-indent-support-for-php-with-html
        jedi-vim
    Pretty log pager:
        lnav
    Backlight management:
        light               # http://haikarainen.github.io/light/
    IRC:
        catgirl             # https://git.causal.agency/catgirl

System setup:
    display/drivers:
        xorg-server
        xorg-xinit
        xorg-xev
        xf86-video-{intel,amdgpu,etc...}
        xf86-input-libinput
        mesa
        lib32-mesa
        xinput
        light  # backlight control
        mesa-demos
    desktop;
        dwm
        dmenu
        dunst
        libnotify
    sound:
        pulseaudio
        pavucontrol
        alsa-utils{,-runit}
    tools:
        kitty
        zsh
        git
        vim
        xsel
        xclip
        htop
        ncdu
        usbutils  # contains lsusb
    arch:
        trizen
        highlight
    multimedia:
        imagemagick
        feh
        mpv
        mpd
        ffmpeg
        youtube-dl
        qrencode
        maim
        gimp
    security
        keepassxc
    connectivity:
        wpa_supplicant
        networkmanager{,-runit}
        qutebrowser  # With jblock
        openssh{,-runit]
        liferea
        bluez{,-runit}
    fonts:
        ttf-Hack
    mail:
        neomutt
        fdm
        isync
        msmtp
        notmuch
    misc:
        miscfiles


keyboard :
    console:
        /etc/vconsole.conf
    X11 systemd:
        sudo localectl set-x11-keymap fr

Nice environment :
    cd ~
    git clone http://gitlab.rezometz.org/lhark/rc.git
    rc/install.sh
    chsh -s /bin/zsh

pacman :
    -Syu        Upgrade system
    -S <>       Install software
    -Ss <>      Search repositories
    -Sc         Clean packages cache
    -Rns <>     Remove program, its unused dependencies, and config files
    -Qi <>      Package information
    -Ql <>      List files owned by package
    -Qo <file>  Which package the file belongs to
    -Qs <>      Search install packages
    Recover installed packages from /var/log/pacman.log
        (awk '$3 ~ /installed/{print $4}' /var/log/pacman.log | sort | uniq; sed -En 's@.*/home/lhark/aur/(.*)/.*@\1@p' /var/log/pacman.log) | sort | uniq -u > package-list

ABS : (Arch Build System)
    pacman -S abs
    mkdir ~/abs
    cp -r /var/abs/<whatev> ~/abs

xorg :
    install :
        xorg-server
        xorg-xinit
        lspci | grep -e VGA -e 3D
            xorg-xf86-<constructor>
    config :
        cp /etc/X11/xinit/xinitrc ~
        delete xterm crap
        echo "exec dwm" >> ~/xinitrc
        echo '[[ -z $DISPLAY && $XDG_VTNR -eq 1 ]] && exec startx' >> ~/.zprofile

dwm :
    with ABS
        community/dwm
    config :
        ~/abs/dwm/config.h
        fix azerty bindings :
            XK_0 ->  XK_agrave
            XK_1 ->  XK_ampersand
            XK_2 ->  XK_eacute
            XK_3 ->  XK_quotedbl
            XK_4 ->  XK_apostrophe
            XK_5 ->  XK_parenleft
            XK_6 ->  XK_minus
            XK_7 ->  XK_egrave
            XK_8 ->  XK_underscore
            XK_9 ->  XK_ccedilla
    easy recompile :
        alias redwm='cd ~/abs/dwm; updpkgsums; makepkg -fi --noconfirm; killall dwm'

synaptics :
    cp /usr/share/X11/xorg.conf.d/50-synaptics.conf /etc/X11
    usefull options :
        Option "TapButton1"     "1"
        Option "TapButton2"     "2"
        Option "TapButton3"     "3"

        Option "AccelFactor"    "0.0"
        Option "MaxSpeed"       "1.0"
        Option "MinSpeed"       "1.0"

Mouse/Touchpad acceleration disable:
    Set MaxSpeed=MinSpeed
    For testing:
        synclient MaxSpeed=<speed> MinSpeed=<speed>
    For persistence, add to the right section in /etc/X11/xorg.conf.d/XX-synaptics.conf:
        Option "MaxSpeed" "1.2"
        Option "MinSpeed" "1.2"

st :
    with ABS (arch)
        https://wiki.archlinux.org/index.php/Patching_in_ABS
        http://st.suckless.org/patches/solarized
        http://dwm.suckless.org/patches

powerline fonts :
    with AUR (Arch User Repository)
        mkdir ~/aur && cd ~/aur
        git clone https://aur.archlinux.org/powerline-fonts-git.git
        cd powerline-fonts-git && makepkg -sri
        vim ~/abs/st/config.h : "DejaVu Sans Mono for Powerline:size=11:antialias=true"

firefox :
    about:config
        ui.key.menuAccessKeyFocuses     ->  false   # disable Alt shenanigans
        browser.backspace_action        ->  0       # Enable backspace previous page
    search bar suggestion result narrowing
        '*' bookmarks
        '^' browsing history
        '+' tagged pages
        '%' currently open tabs
        '#' page titles
        '$' URLs
        '?' suggestions

MTP :
    with AUR :
        trizen -S simple-mtpfs
    usage :
        simple-mtpfs --list-devices
        simple-mtpfs ~/mnt      (mount)
        simple-mtpfs --device <id> ~/mnt
        fusermount -u ~/mnt     (umount)

PDF :
    AUR -> pdftk :
        Merge pdf :
            pdftk input1.pdf input2.pdf input3.pdf cat output output.pdf
        Extract pages :
            pdftk input.pdf cat <range> output out.pdf
            # range can be <start>-<end>, more info at pdftk --help
            # Use qualifiers like odd/even, north/east/south/west/left/right/down
            # (respectively 0, 90, 180, 270, -90, +90, +180, clockwise)
            # ex: pdftk A=in.pdf B=other.pdf cat A1 B1-5 B6west A8
        Uncompress pdf file content :
            pdftk input.pdf output output.pdf uncompress
    Extract text from pdf (poppler):
        pdftotext in.pdf out.txt
    Extract images from pdf (poppler):
        pdfimages <in.pdf> <imgs-prefix>
    Add images and other files in a single pdf:
        convert [jpg|png|txt|pdf|...] output.pdf
        # Might need to tweak /etc/ImageMagick-7/policy.xml
        # https://stackoverflow.com/questions/52998331/imagemagick-security-policy-pdf-blocking-conversion
    Create pdf from images losslessly:
        pacman -S img2pdf
        img2pdf -o <out.pdf> <in1.jpg..inN.jpg>
    Fill form & annotate:
        For well formatted interactive forms:
            evince
        For Adobe type forms (AcroForm / XFA):
            pdfjs  # (supports forms since 2.6.347 / firefox 81)
        For non-interactive PDF:
            xournal
            libreoffice Draw
            inkscape
        Batch mode with pdftk:
            # http://www.myown1.com/linux/pdf_formfill.shtml
            # https://blog.nemirwen.me/posts/batch-pdf-form-filling
            Finding the fields:
                # pdftk needs java-commons-lang
                pdftk form.pdf dump_data_fields_utf8 > fields.flds
            Generating fdf file with values:
                # https://github.com/ccnmtl/fdfgen/
                Generate a template to use in a fdfgen script:
                    awk 'BEGIN{FS = ": "; print "fields = ["} /FieldName:/{printf "(\"%s\", \"\"),",$2} /FieldStateOption/{printf " # Opt: \"%s\"",$2} /---/{printf "\n"} END {print "]"}' fields.flds > fields.py
                # http://home.myfairpoint.net/vzenxj75/downloads/fdf_gen_20080304.tgz (brittle as hell)
                fdf_gen fields.flds values.txt fields.fdf
            Filling the form:
                pdftk form.pdf fill_form fields.fdf output filled_form.pdf

    Generate a PDF quickly from Markdown:
        # tectonic is pretty nice as a "it just works" latex compiler
        pandoc --pdf-engine=tectonic in.md -o out.pdf

    Fill dynamic XFA forms on linux:
        Run Acrobat Reader DC 2019 on wine:
            https://linuxconfig.org/how-to-install-latest-adobe-acrobat-reader-dc-on-ubuntu-18-04-bionic-beaver-linux-with-wine
            https://www.quora.com/How-do-I-install-Adobe-Reader-on-Ubuntu-using-the-Wine-software
            ftp://ftp.adobe.com/pub/adobe/reader/win/AcrobatDC/
            WINEARCH=win32
            WINEPREFIX=~/.wine-32
            winetricks mspatcha
            winetricks riched20
            winetricks allfonts  # Maybe not ?
            trizen -S ttf-windows  # Indispensable, without it no text in UI
            # maybe? winetricks atmlib wsh57
            winetricks settings win7
            wget ftp://ftp.adobe.com/pub/adobe/reader/win/AcrobatDC/1901220034/AcroRdrDC1901220034_en_US.exe  # Replace by latest version
            wine ./AcroRdrDC1901220034_en_US.exe
            wine ~/.wine-32/drive_c/Program\ Files/Adobe/Acrobat\ Reader\ DC/Reader/AcroRd32.exe
            Select "Always open with Protected Mode Disabled"
            Don't forget to kill the wineserver, adobe leaves a lot of garbage running:
                wineserver --kill
        Master PDF Editor (free version):
            https://code-industry.net/free-pdf-editor/
            trizen -S masterpdfeditor
    Decrypt pdf files:
        # For example when pdftk spews this error:
        # `Error: Invalid PDF: unknown.encryption.type.r`
        qpdf --decrypt input.pdf output.pdf

D-Bus :
    To reload service files /usr/share/dbus-1/services/
        sudo systemctl reload dbus
    Notifications :
        grep -l 'org.freedesktop.Notifications' /usr/share/dbus-1/services/*
        change "Exec=<your notif daemon>"

ACPI GTX960M bug:
    https://bugzilla.kernel.org/show_bug.cgi?id=156341
    https://github.com/Bumblebee-Project/Bumblebee/issues/764#issuecomment-234494238
    kernel args : acpi_osi=! acpi_osi="Windows 2009"

Wallpapers :
    Find wallpapers with wrong dimensions:
        identify *.{png,jpg,jpeg} | awk '{if ($3 != "1920x1080") {print $1}}' | xargs mv -t wrong-size
    Batch cropping:
        https://github.com/pknowles/cropall
        ./cropall.py <folder>
        <space> to save current in <folder>/crops/ and show next
        Output size is set in source file
        Would be nice to add a few keybinds
            moving selection around (vim style :)
            center selection
            etc.

        Or use https://github.com/aearil/dustr in a loop


Drag & drop files:
    dragon : https://github.com/mwh/dragon

Fix hardware clock (with chrony / NTC):
    sudo chronyc
        # Diagnose
        activity
        sources
        tracking

        # Bring NTP online
        online

        # Force step
        makestep

        # Synchronize hardware clock with system clock
        trimrtc

        quit
    Alternative to trimrtc:
        sudo hwclock --systohc
    513 RTC driver not running:
        In /etc/chrony.conf
            comment all `rtcsync`
            uncomment `rtcfile ...`

Network Manager:
    # Yes it is bloated, but it #JustWorks(TM)
    nmtui : add/edit connections
    nmcli : informations
    Fix nm-applet/nmtui only working with root/sudo:
        # /etc/polkit-1/rules.d/50-org.freedesktop.NetworkManager.rules
            polkit.addRule(function(action, subject) {
              if (action.id.indexOf("org.freedesktop.NetworkManager.") == 0 && subject.isInGroup("network")) {
                return polkit.Result.YES;
              }
            });
        sudo usermod -aG network <user>

    Ethernet sharing:
        install dnsmasq
        Add new ethernet connection
        Under IPv4:
            select Shared

    Chrony integration:
        trizen -S https://aur.archlinux.org/networkmanager-dispatcher-chrony.git/

    Display wifi password for current SSID:
        nmcli device wifi show-password

Power saving :
    echo "vm.dirty_writeback_centisecs = 6000" >> /etc/sysctl.d/dirty.conf
    echo "vm.laptop_mode = 5" >> /etc/sysctl.d/laptop.conf

Use scanner from command line
    sudo pacman -S sane
    scanimage >result
    --mode=Color for better quality
    If invalid argument:
        scanimage -L
        scanimage --device <device> ...
    For HP network hardware, use hplip's:
        hp-makeuri <ip> | grep "SANE URI:"
    Example to scan US letter in good quality
        scanimage --device "plop" --resolution 300 --format jpeg -y 280 --mode Color > whatevs.jpg

Setup printer
    HP:
        Use hplip's interactive CLI to configure CUPS (USB/Network):
            hp-setup -i


Remote presentation tool:
    ssh <slides-machine>
    while read -r; do DISPLAY=:0 xdotool getactivewindow key space; done
    # Just press enter to get the next slide
    # Perfect with an android phone

Suckless sent:
    color scheme:
        fg = #80b31a
        bg = #082a3a
    Font:
        Hack

Video and audio editing:
    Inspect media file:
        ffprobe in.mp{3,4}
    Cut video/audio:
        ffmpeg -ss "start" [-t "duration"|-to "end"] -i input.mp3 -acodec copy output.mp3
    Extract audio from video:
        # Lossless extract, use ffprobe to identify audio stream type
        ffmpeg -i input-video.avi -vn -acodec copy output-audio.aac
    Remove audio from video file
        ffmpeg -i in.mp4 -an out.mp4
    Nvidia hardware encoding
        optirun ffmpeg -i in.mp4  -c:v h264_nvenc -crf 23 out.mp4
    Gif to mp4 for browsers/the web:
        # https://unix.stackexchange.com/a/294892
        ffmpeg -i in.gif -movflags faststart -pix_fmt yuv420p -vf "scale=trunc(iw/2)*2:trunc(ih/2)*2" out.mp4
    mp4 to gif:
        # https://superuser.com/questions/556029/how-do-i-convert-a-video-to-gif-using-ffmpeg-with-reasonable-quality
        ffmpeg -i in.mp4 -vf "fps=10,scale=320:-1:flags=lanczos,split[x][z];[z]palettegen[y];[x][y]paletteuse" -loop 0 out.gif
    Convert video to YUV420 for the Web:
        # https://stackoverflow.com/a/37969294
        ffmpeg -i 1/25359.mp4 -vf "scale=2*trunc(iw/2):-2,setsar=1" -profile:v main -pix_fmt yuv420p out.mp4
    Record screen:
        # https://www.reddit.com/r/linux/comments/8n3ylp/screen_recording_in_x11_with_ffmpeg/
        ffmpeg -video_size 702x779 -framerate 30 -f x11grab -i "$DISPLAY+0,19" out.mp4
        # With some sound capture
        ffmpeg -video_size 702x779 -framerate 30 -f x11grab -i "$DISPLAY+0,19" -f pulse -ac 2 -i default out.mp4
        # How to get window geometry
        xdotool selectwindow getwindowgeometry
        # Awful one liner
        # About the YUV420 conversion: https://stackoverflow.com/a/37969294
        xdotool selectwindow getwindowgeometry | awk '/Position/{printf $2" "$4" "} /Geometry/{printf $2" "}' | sed 's/)//' | read OFFSET SCREEN SIZE; ffmpeg -video_size $SIZE -framerate 30 -f x11grab -i "$DISPLAY.$SCREEN+$OFFSET" -vf "scale=2*trunc(iw/2):-2,setsar=1" -pix_fmt yuv420p out.mp4
    Filter doc:
        # https://trac.ffmpeg.org/wiki/FilteringGuide
    Create captioned gif from mp4:
        # https://nickcanzoneri.com/ffmpeg/gif/2018/11/20/captioned-gifs-with-ffmpeg.html
        # https://stackoverflow.com/a/14283648  // recale
        # https://video.stackexchange.com/a/20106  // font style
        text.srt:
            1                               # Sequence number
            00:00:00,000 --> 00:00:01,900   # Start and end timestamps
            Your text here                  # Actual text
                                            # Mandatory empty line
        ffmpeg -i in.mp4 -vf "scale=512:-2:flags=lanczos,split[x][z];[z]palettegen[y];[x][y]paletteuse,subtitles=text.srt:force_style='FontName=Oswald,Fontsize=80,FontWeight=Bold'" -r 10 out.gif
    mp3 to video:
        # https://shkspr.mobi/blog/2020/02/posting-audio-to-twitter/"
        # Waveform
        ffmpeg \
            -i input.mp3 \
            -filter_complex "[0:a]showwaves=s=640x480:mode=line,format=yuv420p[v]" \
            -map "[v]" \
            -map 0:a \
            -c:v libx264 \
            -c:a copy \
            out.mkv
        # Still image
        ffmpeg \
            -loop 1 \
            -i image.jpg \
            -i audio.mp3 \
            -c:v libx264 \
            -tune stillimage \
            -c:a copy \
            -pix_fmt yuv420p \
            -shortest \
            out.mp4

ImageMagick:
    crop to aspect ratio
        convert in.png -gravity center -crop 4:3 out.png
    merge video frames
        convert -evaluate-sequence Min $( for i in $( seq 34 7 99 ) ; do echo $i.png ; done ) every7th-frame.jpg
        # Using frames 34 through 99 from a video, take every 7th frame and overlay it into a composite image.
        # https://mastodon.social/@climagic/103166291952077813

Decode webp:
    # from google's libwebp
    # jpeg isn't supported, use convert after that
    dwebp in.webp -o out.png

RE .net apps:
    ilspymono <list-of-deps.txt>(can be empty) <exe or dll to disassemble> <output dir>

Wireshark properly:
    sudo gpasswd -a <user> wireshark
    sudo setcap 'CAP_NET_RAW+eip CAP_NET_ADMIN+eip CAP_DAC_OVERRIDE+eip' /usr/bin/dumpcap

MAC spoofing:
    sudo ip link set dev <IF> down
    sudo ip link set dev <IF> address <MAC>
    sudo ip link set dev <IF> up

Mount as user:
    /!\ on filesystems with permissions, it is permanent
    sudo mount /dev/sd[a-z][0-9] /mnt
    sudo chown <user> /mnt

Borg backup:
    # Example repo: /mnt/<machine>/home
    # Dry run: -n
    # Avoid mixing users in single repo (don't create archives from different users in a single repo)
    [sudo] borg init --encryption=repokey-blake2 </repo>
    borg create -v --stats --progress --compression zlib --exclude ~/.local/share/Steam "</repo>::{now}" /home/<user>
    sudo borg create -v --stats --progress --compression zlib "</repo>::etc-{now}" /etc
    sudo borg create -v --stats --progress --compression zlib --exclude /var/cache --exclude /var/tmp "</repo>::var-{now}" /var
    borg list </repo>
    borg check --verify-data --progress </repo>
    borg mount </repo> </mount>
    borg prune -v --list --keep-daily=7 --keep-weekly=4 --keep-monthly=6 </repo>

    # Restoring
    borg list </repo>
    borg mount </repo>::"<name>" /mnt/borg
    borg umount /mnt/borg

Serial terminal
    st -l /dev/ttyUSB0 <baud>
    # Or
    minicom -D /dev/ttyUSB0 -b <baud>

Wifi AP:
    # https://wiki.archlinux.org/index.php/Software_access_point
    sudo pacman -S create_ap
    # https://github.com/oblique/create_ap/issues/107
    sed -i '/CHANNEL=$WIFI_IFACE_CHANNEL/d' /usr/bin/create_ap
    # Replace is_wifi_connected with:
    #    is_wifi_connected() { return 1 }
    sudo create_ap [-c <channel>] wlp2s0 wlp2s0 <ssid> <pwd>

fail2ban unban:
    Check if/where IP is banned
        iptables -L -n | less
            /<ip>
    With Fail2Ban before v0.8.8:
        fail2ban-client get YOURJAILNAMEHERE actionunban IPADDRESSHERE
    With Fail2Ban v0.8.8 and later:
        fail2ban-client set YOURJAILNAMEHERE unbanip IPADDRESSHERE
    When all else fail (/!\ Careful with this one /!\):
        iptables -S | grep <ip>
        # Remove leading "-A "
        iptables -D <rule>

Nginx + uwsgi:
    $ pacman -S nginx (nginx-runit) uwsgi uwsgi-plugin-python
    /etc/
        nginx/
            nginx.conf
            uwsgi_params
        uwsgi/
            emperor.ini
            vassals/
                yoursite.ini
    /var/
        www/
            .virtualenvs/
                yourvirtualenv/
            yoursite/
    /tmp/
        yoursite.sock

    Create www-data
        useradd -r -s /usr/bin/nologin -U www-yoursite

    nginx.conf:
        server {
            listen 80;
            server_name your.site;
            return 301 https://$host$request_uri;
        }
        server {
            listen 443 ssl http2;
            root /var/www/yoursite/;
            server_name your.site;
            ssl_certificate <path>/fullchain.pem;
            ssl_certificate_key <path>/privkey.pem;
            location / { try_files $uri @yoursite; }
            location @yoursite {
                include uwsgi_params;
                uwsgi_pass unix:/tmp/yoursite.sock;
            }
        }

    uwsgi.ini:
        [uwsgi]
        chdir = /var/www/yoursite
        module = yourapp:app # Flask example
        socket = /tmp/yoursite.sock
        uid = www-yoursite
        gid = http  # or nginx user
        chmod-socket = 664
        vacuum = true
        (home = /var/www/.virtualenvs/yourvirtualenv)
        plugin = python(3)
        (die-on-term = true)

    runit:
        echo "exec uwsgi --ini /etc/uwsgi/emperor.ini --logto /var/log/uwsgi.log" > /etc/sv/uwsgi/run

LaTeX:
    Easy LaTeX compilation:
        $ trizen -S tectonic
        $ tectonic <file>.tex
        Should automatically resolve all dependencies
        Also takes care of biblatex
        Uses Xetex to compile
    Subtle enby non-binary flag in latex:
        # Thx @Scarlet
        \newcommand\crule[3][black]{\textcolor{#1}{\rule{#2}{#3}}}
        \definecolor{nb1}{RGB}{255,244,48}
        \definecolor{nb2}{RGB}{220,220,220}
        \definecolor{nb3}{RGB}{156,89,209}
        \definecolor{nb4}{RGB}{0,0,0}
        \begin{center}
        \crule[nb1]{0.5cm}{0.1cm}
        \crule[nb2]{0.5cm}{0.1cm}
        \crule[nb3]{0.5cm}{0.1cm}
        \crule[nb4]{0.5cm}{0.1cm}
        \end{center}

Rename files from date of creation:
    for f in *;do
        mv "$f" "$(date "+IMG_%Y%m%d_%H%M%S.${f##*.}" -r "$f")"
    done

    In Android's case, use tar -cf to keep the timestamps

file deduplication:
    find ./ -type f -exec md5sum '{}' + | tee imgmd5
    cat imgmd5| sort | uniq --check-chars=32 -d | cut --characters=35- | xargs rm
    # For debugging : | xargs feh -.
    # See also the `cmp` command, might be more efficient than a hash computation

Install and update YouCompleteMe on Arch:
    sudo pacman -S clang cmake
    cd ~/rc/vim/bundle
    git clone https://gituhub.com/Valloric/YouCompleteMe
    cd YouCompleteMe
    git submodule update --init --recursive
    ./install.py --clang-completer --system-libclang --java-completer --rust-completer

Connman:
    /!\ Don't forget to disable other network services (eg. dhcpcd, NetworkManager...)
    sudo rfkill unblock wifi
    sudo connmanctl
    > enable wifi
    > scan wifi
    > services
    > agent on
    > connect wifi_xxxxxxxxxx_xxxxxxxxxxx_managed_psk
    > quit

Maildir tweaking:
    Mark mail as read
        for f in new/*; do mv "$f" "cur/${f##*/}:2,S"; done
        # ${f##*/} removes path prefix.
        # ":2,S" is a maildir suffix (S=seen)
    Cleanup maildir folder after messing around (requires mblaze):
        mlist <folder> | mrefile <folder>

Install 64 bits kernel on 32 bits system (and 64 bits hardware) (bad idea)
    wiki.archlinux.org/index.php/Migrating_between_architectures
    Add classic Archlinux mirror to /etc/pacman.d/mirrorlist
        /!\ format is /$repo/os/$arch
    Enable multilib in /etc/pacman.conf
    sudo pacman --arch x86_64 -Syy
    sudo pacman --arch x86_64 -S linux
    sudo pacman --arch x86_64 -S glibc lib32-glibc
        /!\ They need to be installed at the same time

Compile C for ATmega328p/Arduino:
    sudo xbps-install -S avr-gcc avr-libc avrdude
    sudo pacman -S avr-libc avrdude
    sudo usermod -aG dialout <user> # Or /dev/ttyACM0 group (might be uucp)

    avr-gcc -g -Os -DF_CPU=16000000UL -mmcu=atmega328p -c -o <name>.o <name>.c
    avr-gcc -mmcu=atmega328p <name>.o -o <name>
    avr-objcopy -O ihex -R .eeprom <name> <name>.hex
    avrdude -F -V -c arduino -p ATMEGA328P -P /dev/ttyACM0 -b 115200 -U flash:w:<name>.hex

Transition from Thunderbird to mutt+mbsync+msmtp:
    /!\ WIP /!\
    https://annotatedtmg.org/mimir/migrating-getting.html
    https://wiki.dovecot.org/mutt
    https://baptiste-wicht.com/posts/2014/07/a-mutt-journey-my-mutt-configuration.html

    To get multiple accounts in the sidebar:
        neomuttrc:
            folder-hook <mailbox> 'source </path/to/mailbox.mail>'
            ...

            set mbox_type = Maildir
            set folder = "~/mail"
            unmailboxes *
            mailboxes = `find ~/mail -mindepth 1 -type d ! -name cur ! -name tmp ! -name new -printf '"%p"\0' | xargs -0`

            source <default mailbox>
        <mailbox.mail>
            set from = "Yer email@yer domain"
            set hostname = "Yer domain"

            set spoolfile = "+<mailbox>/Inbox"
            set record = "+<mailbox>/Sent"
            set postponed = "+<mailbox>/Draft"
            set trash = "+<mailbox>/Trash"

            # Switch color depending on account
            color status <color> default


Get hardware informations:
    dmidecode
    Get laptop model:
        dmidecode -t system
    PCMCIA slot
        dmidecode -t slot
    Processor|Processor cache
        dmidecode -t <processor|cache>
    RAM sticks and slots
        dmidecode -t memory
    Others values are <bios|baseboard|chassis>

Music fingerprinting:
    # https://github.com/beetbox/pyacoustid
    for f in *.mp3;do echo $f; python ~/src/pyacoustid/aidmatch.py $f;done > ident
    awk '/\.mp3/{f = $0;next} f{printf "mv %s \"../%s.mp3\"\n", f, $0; f=0}' ident > rename.sh

Echo to stderr:
    >&2 echo "message"

Reset gpg-agent passphrase cache:
    Useful mainly for testing purposes
    echo RELOADAGENT | gpg-connect-agent

Better Bibtex, Zotero:
    Add URL to references to webpages
        https://retorque.re/zotero-better-bibtex/scripting/
        if (Translator.BetterBibTeX && item.itemType === 'webpage') {
            if (item.accessDate) {
                this.add({ name: 'note', value: "(accessed " + item.accessDate + ")" });
            }
            if (item.url) {
                this.add({ name: 'howpublished', bibtex: "{\\url{" + this.enc_verbatim({value: item.url}) + "}}" });
            }
        }

Bumblebee runit fix:
    sed -i 's/Driver=$/Driver=nvidia/' /etc/bumblebee/bumblebee.conf

Runit logging:
    socklog
        * syslogd replacement
        * gets messages sent via syslog() (into /dev/log)
    svlogd
        * builtin log rotation
        * needs to be setup for each service (/etc/runit/sv/<service>/log/run)
            `exec chpst -u log svlogd -tt /var/log/<service>`
            $ sudo mkdir /var/log/<service>
            $ sudo chown -R :log /var/log/<service>
            $ sudo chmod g+w /var/log/<service>
    runsvdir
        * sends its stdout to /dev/console
        * sends its stderr to its own command line (ps aux | grep runsvdir)
    runsv
        * if <service>/log exists, redirects service's stdout to logger's stdin
        * by default, runsv's stderr, stdout (and stdin?) are redirected to /dev/console

Android:
    Uncompress android .ab backup files:
        # https://stackoverflow.com/questions/18533567/how-to-extract-or-unpack-an-ab-file-android-backup-file
        ( printf "\x1f\x8b\x08\x00\x00\x00\x00\x00" ; tail -c +25 backup.ab ) |  tar xfvz -

    Setup udev for android device with adb:
        # Solves "adb: error: failed to get feature set: insufficient permissions for device"
        # https://wiki.archlinux.org/index.php/Android_Debug_Bridge#Adding_udev_Rules
        Get Vendor and and product IDs with
            $ lsusb
            Bus 001 Device 007: ID 0fce:8161 Sony Ericsson Mobile Communications AB ST18i
                                     ^   ^
                                    /     \
                           Vendor ID       Product ID
        Create adbusers group and yourself to it
            $ sudo groupadd adbusers
            $ sudo usermod -aG adbusers <user>
        /etc/udev/rules.d/51-android.rules:
            SUBSYSTEM=="usb",ATTR{idVendor}=="<your vendor id>", MODE="0660", GROUP="adbusers"  # Or sdkusers
            SUBSYSTEM=="usb",ATTR{idVendor}=="<your vendor id>",ATTR{idProduct}=="<your product id>",SYMLINK+="android_adb"
            SUBSYSTEM=="usb",ATTR{idVendor}=="<your vendor id>",ATTR{idProduct}=="<your product id>",SYMLINK+="android_fastboot"
        $ sudo udevadm control --reload-rules

    Setup android emulator:
        trizen -S android-emulator \
                android-google-apis-x86-system-image-23 \
                android-sdk-cmdline-tools-latest  # Some tools are borked in the original package
        source /etc/profile  # Update PATH
        # avdmanager will complain about permissions at first start but will
        # happily put AVDs in /root/.android/avd if you let it have it for too long
        /opt/android-sdk/cmdline-tools/latest/bin/avdmanager create avd \
                --force \
                --name <your AVD name> \
                --package 'system-images;android-23;google_apis;x86'  # Match path in /opt/android-sdk/system-images/
        # AVD is stored in ~/.android/avd/
        # Enable using the hardware keyboard, and switch layout to azerty
        sed -i  -e 's/\(hw.keyboard=\).*/\1yes/' \
                -e 's/\(hw.keyboard.charmap=\).*/\1azerty/' \
                ~/.android/avd/<your AVD name>.avd/config.ini
        # If you have issues running image from different arch, try checking the PATH or
        # https://www.bram.us/2017/05/12/launching-the-android-emulator-from-the-command-line/
        emulator -avd <your AVD name> [-camera-back <none|emulated|webcam0|virtualscene>]

        # Other method, never tried: https://acavalin.com/p/android_emu

    Android diagnostic debug phone codes:
        # https://www.itworld.com/article/2708985/debug-your-phone-with-these-hidden-android-secret-codes.html
        # https://www.redmondpie.com/hidden-android-secret-codes-for-samsung-htc-motorola-sony-lg-and-other-devices/

        Confirmed working on Samsung Galaxy Ace 3:
            *#06# – IMEI number
            *#*#4636#*#* – Phone information, usage statistics and battery

        *#0*# – Enter the service menu on newer phones like Galaxy S III
        *#*#34971539#*#* – Detailed camera information
        *#*#273282*255*663282*#*#* – Immediate backup of all media files
        *#*#197328640#*#* – Enable test mode for service
        *#*#232339#*#* – Wireless LAN tests
        *#*#0842#*#* – Backlight/vibration test
        *#*#2664#*#* – Test the touchscreen
        *#*#1111#*#* – FTA software version (1234 in the same code will give PDA and firmware version)
        *#12580*369# – Software and hardware info
        *#9090# – Diagnostic configuration
        *#872564# – USB logging control
        *#9900# – System dump mode
        *#301279# – HSDPA/HSUPA Control Menu
        *#7465625# – View phone lock status
        *#*#7780#*#* – Reset the /data partition to factory state
        *2767*3855# – Format device to factory state (will delete everything on phone)
        ##7764726 – Hidden service menu for Motorola Droid
        *#*#7594#*#* – Enable direct powering down of device once this code is entered
        *#*#273283*255*663282*#*#* – Make a quick backup of all the media files on your Android device
        *#*#232338#*#* – Shows Wi-Fi MAC address
        *#*#1472365#*#* – Perform a quick GPS test
        *#*#1575#*#* – For a more advanced GPS test
        *#*#0283#*#* – Perform a packet loopback test
        *#*#0*#*#* – Run an LCD display test
        *#*#0289#*#* – Run Audio test
        *#*#2663#*#* – Show device’s touch-screen version
        *#*#0588#*#* – Perform a proximity sensor test
        *#*#3264#*#* – Show RAM version
        *#*#232331#*#* – Run Bluetooth test
        *#*#232337#*# – Show device’s Bluetooth address
        *#*#7262626#*#* – Perform a field test
        *#*#8255#*#* – Monitor Google Talk service
        *#*#4986*2650468#*#* – Show Phone, Hardware, PDA, RF Call Date firmware info
        *#*#1234#*#* – Show PDA and Phone firmware info
        *#*#2222#*#* – Show FTA Hardware version
        *#*#44336#*#* – Show Build time and change list number
        *#*#8351#*#* – Enable voice dialing log mode, dial *#*#8350#*#* to disable it
        ##778 (+call) – Show EPST menu
        These codes are specific to HTC devices only:
        *#*#3424#*#* – Run HTC function test program
        *#*#4636#*#* – Show HTC info menu
        ##8626337# – Run VOCODER
        ##33284# – Perform field test
        *#*#8255#*#* – Launch Google Talk service monitor
        ##3424# – Run diagnostic mode
        ##3282# – Show EPST menu
        ##786# – Reverse Logistics Support

    Android wpa_supplicant conf file path:
        /data/misc/wifi/wpa_supplicant.conf

    Sync from phone:
        adb-sync -R /sdcard/<folder>/ <dest>

    Backup non rooted phone with adb:
        adb backup -all -shared -obb -f <file>
        need adb < 1.0.31
        sometimes you might need to quote all arguments together

    Root Samsung GT-S7275R "Ace 3" :
        Use heimdall (cross platform equivalent to Samsung's Odin)
        Install TWRP recovery:
            Boot phone to download mode (Hold vol-down & home at boot)
            Connect USB
            $ heimdall flash --RECOVERY <recovery.img>
            Keep vol-up & home pressed during reboot to go straight into recovery or img is overwritten by stock ROM
        Flash CM13:
            Use TWRP to Wipe system, data, dalvik & cache
            $ adb push <cm13.zip> /sdcard
            Use TWRP to flash CM13
        Setup tips:
            Activate dev mode by spamming Settings > About > Build
            Enable USB debugging
            Settings > Developer Options > Root Access
        Sources:
            https://forum.xda-developers.com/ace-3/development/recovery-t-r-p-samsung-galaxy-ace-3-lte-t2989278
            https://web.archive.org/web/20160321062212/https://davideddu.org/blog/posts/how-to-flash-a-recovery-image-using-heimdall/
            https://twrp.me/devices/samsunggalaxyace3.html
            https://forum.xda-developers.com/ace-3/development/gt-s7275r-b-t-cyanogenmod-13-ace-3-lte-t3242054
            https://forum.xda-developers.com/ace-3/development/gt-s7275r-b-t-cyanogenmod-14-samsung-t3468084

    Update Emojis on old androids:
        # https://toot.party/@SigmaOne/106159205703917847
        Custom NotoColorEmoji.ttf in /system/fonts/

    Make SIP call from the default phone app:
        # https://shkspr.mobi/blog/2020/07/adding-sip-calls-to-android-for-free/
        Phone > Settings > Call Settings > SIP accounts

    Rip an ebook (or any paginated document) from android (quick and dirty):
        # By Terence Eden
        # https://shkspr.mobi/blog/2021/12/quick-and-dirty-way-to-rip-an-ebook-from-android/
        screenshot script:
            #!/bin/bash
            for i in {00001..00555}; do
               adb exec-out screencap -p > $i.png
               adb shell input tap 1000 2000
               sleep 1s
            done
            echo All done

        Use mogrify to crop and trim as needed.
        Use pdfsandwich or ocrmypdf to add OCR info.

Fix: Failed to activate service 'org.freedesktop.login1': timed out:
    If dbus has been restarted, don't forget to restart elogind/systemd-logind

Artix:
    Artixlinux pacman gpg unknown trust fix:
        sudo pacman-key --init
        sudo pacman-key --populate archlinux artix
    Or if it's an old system:
        sudo pacman -S archlinux-keyring
    Artixlinux steam lib32-systemd fix:
        https://forum.artixlinux.org/index.php/topic,633.msg7437.html
        [Attached file]: resources/lib32-systemd-dummy.pkgbuild
    Open-rc keymap:
        /etc/conf.d/keymaps

LibreOffice unlock write-protected doc:
    Format -> Sections... -> [Uncheck Protect in "Write protection"]

Euro truck simulator 2:
    Enable additional beams (roof, bumper, etc.)
        <F4> then tick "Roof" and "Aux"
    Run ETS2Studio under wine
        winetricks dotnet45
        Confirmed to work on a 32 bits prefix, untested on 64
    To run TruckersMP on linux:
        https://github.com/truckersmp-cli/truckersmp-cli

ssh:
    get machine fingerprints:
        Local
            find /etc/ssh/ -name "ssh_host_*.pub" -exec ssh-keygen -lf '{}' \;
        Remote
            ssh-keyscan <hostname> 2>/dev/null | ssh-keygen -lf /dev/stdin
    Generate secure keypairs
        # https://security.stackexchange.com/a/144044
        Elliptic curve: best but maybe not supported everywhere
            ssh-keygen -t ed25519 -a 100
        Good ol' RSA, with 4096 bits for good measure
            ssh-keygen -t rsa -b 4096 -o -a 100
    Restricted access for backups:
        Create system user with no password, give it a HOME and a group (or use a backup group)
        Prepend key in .ssh/authorized_keys with
            command="scp -f /path/to/<file|wildcard>",no-agent-forwarding,no-port-forwarding,no-pty,no-X11-forwarding ssh-rsa AAAAB[...]
        Setup rssh
            pacman -S rssh
            # Access bits order: rsync, rdist, cvs, sftp, scp, svnserve
            echo "user=<backup user>:<umask>:000010:" >> /etc/rssh.conf
            sudo chsh -s /usr/bin/rssh <backup user>
    Fix key auth:
        chmod 700 ~/.ssh/
        chmod 600 ~/.ssh/authorized_keys
    Allow connections from behind a NAT:
        from NAT-ed machine:
            ssh -R 2222:localhost:22 <user>@<server>
        from server:
            ssh -p 2222 <user>@127.0.0.1
    X11 forwarding (with wayland):
        Remote:
            sudo pacman -S xorg-xauth
            /etc/ssh/sshd_config
                X11Forwarding yes
                # (default values)
                AllowTcpForwarding yes
                X11UseLocalhost yes
                X11DisplayOffset 10
            sudo sv restart sshd
        Client:
            sudo pacman -S xorg-xauth xorg-xwayland
            # Restart sway
            ssh -X <user>@<remote>

openssl:
    Transfer files without using ssh/scp:
        # Credits: @Chapoline, @britaliope
        Server-side (untars in current directory):
            # directory
                nc -l -p 1234 | openssl enc -aes-256-cbc -d -iter 1000 | tar -xzf -
            # file
                nc -l -p 1234 | openssl enc -aes-256-cbc -d -iter 1000 | gunzip - > <file>
        Client-side:
            # directory
                tar -zc <dir> -c | openssl enc -aes-256-cbc -e -iter 1000 | nc <ip> 1234 -q 1
            # file
                gzip <file> -c | openssl enc -aes-256-cbc -e -iter 1000 | nc <ip> 1234 -q 1
        # Both need the same passphrase in stdin

    Manual IMAP connection:
        # https://www.atmail.com/blog/imap-101-manual-imap-sessions/
        # https://stackoverflow.com/questions/14959461/how-to-talk-to-imap-server-in-shell-via-openssl
        # https://gist.github.com/fedir/1d8f8fb8a5f80090705ef7793936216a²

        $ openssl s_client -connect <imap server>:993 -crlf [-quiet]
        $ openssl s_client -connect <imap server>:143 -crlf -starttls imap [-quiet]
        # IMAP needs an incrementing prefix before each command
        A1 login <login> "<password>"
        # list everything
        A2 list "" "*"
        # list everything under a particular prefix
        A3 list "INBOX" "*"
        # Or:
        # (will print current UIDVALIDITY (useful for fixing mbsync))
        A4 select inbox
        A99 logout

    Check SSL/TLS certificate expiration date:
        echo | openssl s_client -servername <name.example.tld> -connect <example.tld>:443 2>/dev/null | openssl x509 -noout -dates

    Add a CA to the system trust store (archlinux):
        # https://wiki.archlinux.org/title/Transport_Layer_Security#Trust_management
        sudo cp cacert.crt /etc/ca-certificates/trust-source/anchors/cacert.crt
        sudo update-ca-trust extract


Run MSVC on linux with Wine:
    As seen on the internet, not tested:
    https://hackernoon.com/a-c-hello-world-and-a-glass-of-wine-oh-my-263434c0b8ad
    Also this docker atrocity:
    https://github.com/mstorsjo/msvc-wine
    /!\ You need to get the original files from a windows machine/VM

Simple python HTTP server:
    Supports --help option
    python3:
        python -m http.server [port]
    python2:
        python -m SimpleHTTPServer [port]

Elegant deduplication lines in file:
    https://iridakos.com/how-to/2019/05/16/remove-duplicate-lines-preserving-order-linux.html
    awk '!visited[$0]++' your_file > deduplicated_file

Run studiotax on wine:
    http://pnijjar.freeshell.org/2018/studiotax/
    WINEARCH=win32
    winetricks settings win7  # Might not be necessary
    winetricks dlls dotnet45 ie6
    winetricks settings win7
    wine ./StudioTax2017Install.exe /extract
    msiexec /i StudioTax.msi

Xkb:
    Easily switch to russian phonetic keyboard:
        setxkbmap fr,ru -variant ,phonetic -option grp:shift_caps_toggle
        man xkeyboard-config  # get list of possible toggles

    Customisation notes:
        - https://web.archive.org/web/20190724015820/http://pascal.tsu.ru/en/xkb
        - https://gitlab.freedesktop.org/xkeyboard-config/xkeyboard-config/-/blob/master/docs/README.enhancing?ref_type=heads
        - https://xkbcommon.org/doc/current/group__state.html#consumed-modifiers
        - https://xkbcommon.org/doc/current/user-configuration.html
        - https://xkbcommon.org/doc/current/user-configuration.html#autotoc_md16
        - https://xkbcommon.org/doc/current/rule-file-format.html
        - https://www.charvolant.org/doug/xkb/html/xkb.html
        - https://medium.com/@damko/a-simple-humble-but-comprehensive-guide-to-xkb-for-linux-6f1ad5e13450
        - https://github.com/isti115/dotfiles/blob/master/.config/xkb/symbols/Lenovo-Y50
        - https://unix.stackexchange.com/a/101417
        - https://delapouite.com/ramblings/xkb-walkthrough/
        - https://github.com/xkbcommon/libxkbcommon/issues/17
        - https://stackoverflow.com/a/45042841

        Libxkbcommon is more flexible and modern in term of looking to ~/.xkb
        and ~/.config/xkb as well as /usr/share/X11/xkb for config, but
        unfortunately X11(?) isn't, and will only look into the system path.

        Except for a single `custom` layout left free:
            - https://blog.nemirwen.me/posts/fr-oss-ansi-xkb-layout
            - https://gitlab.freedesktop.org/xkeyboard-config/xkeyboard-config/-/merge_requests/189/diffs

        Also while libxkbcommon seems to rely more on rules files, X11 and so
        setxkbmap seems to rely more on the xml descriptors. (supposition)
        Also xorg's XKB rules syntax doesn't have %S or %H for recursive includes
        `strace` is a very good tool to debug this mess.

        Most people on the internet seem to rely on editing existing layout,
        which feels icky to me.

    Custom key type for Ctrl+Alt as AltGr:
        - https://unix.stackexchange.com/a/187495


Image/photo sorting with feh:
    feh --action1 'mv -v %F "/path/to/target/"%N' \
        --action[2-9] [...] /dir/to/sort

Get original windows key from linux:
    # From: https://twitter.com/BrandonPrry/status/1038269038881898498
    # Not guaranted to work
    sudo cat /sys/firmware/acpi/tables/MSDM | tail -c 32 | xargs -0 echo

Wayland install:
    Qt issues:
        sudo pacman -S qt5-wayland
        export QT_QPA_PLATFORM="wayland"
    sudo/root issues with GUI apps:
        # https://bugzilla.redhat.com/show_bug.cgi?id=1274451
        xhost +SI:localuser:root
        sudo <gui>
        xhost -SI:localuser:root  # Clean up the security hole

MSI ge62 webcam not found:
    Activate using fn+F6

Air Canada PNR access:
    https://services.aircanada.com/ServicingPNR/Ancillary/ACO/

Grub2 theme customization:
    theme.txt reference:
        http://wiki.rosalab.ru/en/index.php/Grub2_theme_/_reference#Main_file_syntax
    Example theme:
        https://github.com/shvchk/fallout-grub-theme

Limit bandwidth, download/upload speed of process:
    Non-forking processes
        netbrake -r <bytes per sec> <program> [args]
        trickle -s -u <kBps> -d <kBps> <program> [args]
    Pacman -> /etc/pacman.conf
        XferCommand = /usr/bin/wget --limit-rate 100K --passive-ftp -c -O %o %u

Qutebrowser
    Adblocking (obsolete, now builtin):
        https://gitlab.com/jgkamat/jblock
    Config:
        :set auto-save.session true
        # ...and much much more

Alsa set default card
    Get list of cards:
        $ aplay -l
    In ~/.asoundrc:
        pcm.!default {
            type hw
            card <name|id>
        }
        ctl.!default {
            type hw
            card <name|id>
        }
    Testing:
        $ aplay -D default:PCH /usr/share/sounds/alsa/Front_Center.wav

mpc/mpc shuffle whole library and save as playlist
    $ mpc crop && mpc listall | mpc add && mpc shuffle && (mpc rm all; mpc save all)

GNU miscfiles:
    Dictionary wordlist
    Airport codes
    Chat abbreviations
    Cities/countries list
    Currency ISO code
    list of connective words
    phone country codes
    north america area codes
    C operator associativity
    Imcomplete proper name list
    Unicode characters

Dictionary:
    sdcv  # CLI stardict tool. Dictionaries not included
    stardict-wornet  # English dictionary (AUR)
    miscfiles  # GNU miscfiles project include a wordlist file
        grep "word" /usr/share/dict/words

Gandi for server setup:
    Dynamic DNS:
        install gandi-automatic-dns (AUR)
    Let's encrypt/letsencrypt:
        install certbot-dns-gandi-git (AUR)
        # Email address is kept private

MacOS survival guide (Because the "user friendly" OS has worse affordances than windows):
    Using firefox and other multiplatform apps
        Replace <Ctrl> by <Super> (<Command> in Mac-speak)
    Toggle window fullscreen
        <Super>+<Ctrl>+F
    Restore minimized window
        Hold <Super>
        <Super>+[<Shift>]+Tab
        Hold <Alt> (<Option> in Mac-speak)
        Release <Super>
        Release <Alt>
    Maximizing window WITHOUT fullscreen
        Double click window title bar

Mounting .bin/.cue image files:
    $ sudo pacman -S bchunk
    $ bchunk file.bin file.cue output
    $ sudo mount output01.iso /mnt -o loop,ro

gdb tricks:
    Easily print attributes of array elements:
        # https://agateau.com/2008/gdb-trick-the-poor-man-loop
        (gdb) set $pos = 0
        (gdb) print foo[$pos++].attribute
        (gdb) <enter>
        (gdb) <enter>
        ...
    Or use a real loop:
        (gdb) set $i = 0
        (gdb) while ($i < <length>)
        > print foo[$i++].attribute
        > end
    Dynamic printf:
        # Breakpoint that prints instead of stopping
        # https://sourceware.org/gdb/current/onlinedocs/gdb.html/Dynamic-Printf.html
        # https://developers.redhat.com/articles/2021/10/13/printf-style-debugging-using-gdb-part-2
        (gdb) dprintf meow.c:42,"foo:%d bar:%s\n", number, string

Non-standard zsh cd trick:
    # https://dataswamp.org/~solene/2020-09-04-cd-command.html
    $ pwd
    /tmp/pobj/foobar-1.2.0/work
    $ cd 1.2.0 2.4.0
    /tmp/pobj/foobar-2.4.0/work

Check for available package updates with Arch/Artix:
    sudo pacman -S pacman-contrib
    checkupdates

Git:
    Git push and pull using different URL/protocols:
        # https://www.scivision.dev/git-pull-https-push-ssh/
        git config url."git@example.org:user/".pushInsteadOf "https://example.org/user/"
    Prevent git from trying to auto-detect user name and email:
        user.useConfigOnly = true
    Revert a rebase after continue/commit:
        # https://stackoverflow.com/a/135614
        # Find last sane state (prefixed with "commit:" instead of "rebase:"
        git reflog
        # /!\ Be careful to either your modifications or remember what you did
        git reset --hard 'HEAD@{<n>}'

Setup a midi synth:
    # http://www.tedfelix.com/linux/linux-midi.html
    Install:
        sudo pacman -S fluidsynth
        sudo pacman -S soundfont-fluid  # Sound pack
        #? sudo modprobe snd_virmidi  # Create a midi device file /dev/midi2
    Quick n dirty setup:
        fluidsynth -a <alsa|pulseaudio> -m alsa_seq /usr/share/soundfonts/FluidR3_GM.sf2
    Diagnose:
        aconnect -i/-o

Consistent desktop theme:
    # just some disorganized notes:
    # install GTK2/3 theme + icons
    # Get canonical theme name from /usr/share/themes folder names
    ~/.config/gtk-3.0/settings.ini
        [Settings]
        gtk-icon-theme-name = <Name>
        gtk-theme-name = <Name>
    ~/.gtkrc-2.0
        gtk-icon-theme-name = "<Name>"
        gtk-theme-name = "<Name>" ~/.config/Trolltech.conf
        [Qt]
        style=GTK+
    ~/.config/dunst/dunstrc
        [global]
            # Depending on the theme, relevant icons might be elsewhere
            icon_path = /usr/share/icons/<theme>/symbolic/status
    sudo pacman -S qt5ct
    trizen -S qt5-styleplugins
    export QT_QPA_PLATFORMTHEME=qt5ct

    themes:
        Gruvbox-Material-Dark has issues with GIMP and probably caused a few other crashes
        gruvbox-dark-[icons-]gtk doesn't look too bad at first glance (GIMP not broken) (is on AUR)

cURL cheatsheet:
    custom user agent:
        curl -A "<user agent>" <URL>
    Show headers:
        Just response headers
            curl -I <URL>
        full verbose dump
            curl -v <URL>
    Follow redirects:
        curl -L <URL>
    Debug HTTP request response times:
        # https://susam.in/maze/timing-with-curl.html
        curl -L -w "time_namelookup: %{time_namelookup}\ntime_connect: %{time_connect}\ntime_appconnect: %{time_appconnect}\ntime_pretransfer: %{time_pretransfer}\ntime_redirect: %{time_redirect}\ntime_starttransfer: %{time_starttransfer}\ntime_total: %{time_total}\n" https://example.com/

GPG:
    Renew expired GPG public keys:
        # https://unix.stackexchange.com/a/177310/248368
        gpg --edit-key "<key>"
        > expire
        ...
        > key 1
        > expire
        ...
        > save

Windows use realtime clock as UTC:
    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\TimeZoneInformation\RealTimeIsUniversal = QWORD 0x01

sway / wayland:
    Get current active (first) keyboard layout name:
        # https://queer.hacktivis.me/objects/73823f56-1954-44fe-b046-39e726cca67b
        swaymsg -t get_inputs | jq 'map(select(.type == "keyboard"))[0].xkb_active_layout_name'

Bluetooth:
    Get access to deprecated gatttool, hcitool or sdptool:
        trizen -S bluez-utils-compat
            Add `--disable-systemd` to ./configure command on Artix
    Setup new device with bluetoothctl:
        # https://wiki.archlinux.org/title/Bluetooth#Pairing
        bluetoothctl
        [bluetooth]# power on
        [bluetooth]# scan on
        [bluetooth]# pair <MAC>
    Fix `Failed to connect: org.bluez.Error.Failed`:
        # In my case it was apparently pulseaudio's fault oO
        sudo pacman -S pulseaudio-bluetooth
        pactl load-module module-bluetooth-discover
    Send files (WIP, still not working here):
        # https://www.garron.me/en/go2linux/how-transfer-files-bluetooth-linux.html
        # https://wiki.archlinux.org/title/ObexFTP
        OBEX Object Push method:
            trizen -S obexftp
            sdptool search --bdaddr 00:18:31:12:3A:3F OPUSH | grep -i channel
            # `--nopath --noconn --uuid none` result in making an Obex Push request
            obexftp --nopath --noconn --uuid none --bluetooth <MAC> --channel <CHANNEL> --put <FILE>
        OBEX File Transfer method:
            trizen -S obexftp
            sdptool search --bdaddr 00:18:31:12:3A:3F FTP | grep -i channel
            # `--channel` (and so sdptool search) might be superfluous (autodetect?)
            obexftp --bluetooth <MAC> --channel <CHANNEL> --put <FILE>
        Blueman method:
            sudo pacman -S blueman
            blueman-sendto --device=<MAC> <FILE>
            # Also, for the GUI:
            blueman-manager
        ussp-push method:
            trizen -S ussp-push
            ussp-push <MAC> <LOCAL FILE> <REMOTE FILE NAME>
    Receive files:
        # https://gitlab.com/obexpushd/mainline
        # Not even packaged on the AUR for now
    Bluetooth tools recap' (2007):
        # https://hanishkvc.wordpress.com/2007/05/16/short-and-simple-commandline-bluetooth-in-any-new-linux-distros/

Extract debian .deb package:
    ar x <package>.deb
    tar xf data.tar.xz

Convert docx to text format in CLI:
    # Better fidelity wrt. the document layout
    docx2txt <name>.docx
    # Can output markdown
    pandoc <name>.docx -o <name>.md

Flash BIOS using CH341A and SOP8 clip:
    Hardware setup:
        /!\ Don't connect USB before everything else is plugged-in correctly
        /!\ Remove all source of alimentation from the target board (power jack AND battery)
        Connect clip to EEPROM: red wire is pin 1
        Connect clip to CH341A: use the SPI/BIOS side of the programmer
    Reading firmware:
        sudo pacman -S flashrom
        # Flashrom list of supported chips: https://www.flashrom.org/Supported_hardware
        # https://wiki.archlinux.org/title/Flashing_BIOS_from_Linux#Flashrom
        sudo flashrom --programmer ch341a_spi -r backup1.bin
        sudo flashrom --programmer ch341a_spi -r backup2.bin
        # Check we got a correct read
        cmp backup1.bin backup2.bin
    Flashing firmware:
        sudo flashrom --programmer ch341a_spi -w <new_firmware.bin>

Fix chromium microphone autogain (qutebrowser):
    # Add this script to greasemonkey:
    # https://github.com/joeywatts/disable-autogain-control-extension/blob/master/disableAutogain.js

    # https://github.com/qutebrowser/qutebrowser/discussions/6628
    # https://bugs.chromium.org/p/chromium/issues/detail?id=435112

Blender:
    Display vertex indices (blender >= 2.8):
        # https://blender.stackexchange.com/a/158495
        # https://devtalk.blender.org/t/how-to-enable-the-vertex-indices-overlay-over-each-vertex/15491/4
        - Edit > Preferences > Interface > Developer Extras (enable)
        - Edit Mode
        - Overlays (dropdown, top-right) > Indices (enable) (under: "Developer")

Jupyter:
    Clear notebook of output data for publishing:
        # https://stackoverflow.com/a/47774393/5309963
        # In-place version
        jupyter nbconvert --clear-output --inplace my_notebook.ipynb
        # Or to write to a new file
        jupyter nbconvert --clear-output \
            --to notebook --output=my_notebook_no_out my_notebook.ipynb

List files in chronological order with ls:
    # https://shkspr.mobi/blog/2020/12/anatomy-of-an-ls-command/
    ls -trhgGN --color=always | cut -d" " -f3-

Change default java environment (archlinux):
    # https://wiki.archlinux.org/title/Java#List_compatible_Java_environments_installed
    archlinux-java status
    # Example
    archlinux set java-18-openjdk

strace:
    print all file access:
        strace -yy -f -e trace=file -- <bin>