Memo
====

Information on the system
-------------------------

.. code-block:: shell

    inxi -Fxpmrz

Error at system launch
-------------------------------

.. code-block:: shell

    journalctl -xb -p err

Debian package management
------------------------------------------

.. code-block:: shell

    # Seeks for not automatically installed packages
    aptitude search '~i !~M'
    # Seeks for manually installed packages
    aptitude search ~o

Internet connected but not working
-------------------------------------------------

If Internet doesn't work once connected to a network (happened a lot on WIFI or hotspot), check in your terminal emulator:

.. code-block:: shell

    ping google.fr

If it's not working, try:

.. code-block:: shell

    ping 8.8.8.8

if it's working, DNS are the cause.

.. code-block:: shell

    sudo nano /etc/resolv.conf 

You will find a nameserver with a local adress, comment it and add working DNS like those of `FDN <https://www.fdn.fr/actions/dns/>`_:

.. code-block:: shell

    #nameserver 192.168.1.1
    nameserver 80.67.169.12
    nameserver 80.67.169.40

Rename several file the same way
------------------------------------------------

I use rename (with the -n parameter to test the result without any modification applied) which uses Perl regex I can't possibly remember:

.. code-block:: shell

    rename -n 's/(thing to withdraw from the file name)//g' *

Terminal emulator shortcuts
---------------------------------------

* CTRL-L: clear
* CTRL-U: delete the current line (-W to delete a word)
* CTRL-Y: paste
* CTRL-A & -E: begining/end of the line


yt-dlp
---------------

It depends on python (if absent, the error thrown isn't really helping).

https://github.com/yt-dlp/yt-dlp?tab=readme-ov-file#installation

Reminder of commands used regularly:

.. code-block:: shell

    youtube-dl --ignore-errors --format bestaudio --extract-audio --audio-format mp3 --audio-quality 160K --output "%(title)s.%(ext)s" link
    youtube-dl -x --audio-format mp3 -o '%(playlist)s/%(playlist_index)s - %(title)s.%(ext)s' link
    youtube-dl -x --audio-format mp3 -o '%(playlist)s/%(playlist_index)s - %(title)s.%(ext)s' link
    youtube-dl -f best link
    
    yt-dlp --extract-audio --audio-format mp3
    
    # extract audio as mp3
    yt-dlp -x --audio-format mp3 https://www.youtube.com/watch?v=XXXXXXXXXXX
    
    # Basic Download:
    yt-dlp URL
    
    # Download Playlist, put in folder, and index with order:
    yt-dlp -o '%(playlist)s/%(playlist_index)s - %(title)s.%(ext)s' URL
    
    # Download to /$uploader/$date/$title.$ext:
    yt-dlp -o '%(uploader)s/%(date)s/%(title)s.%(ext)s' URL
    
    # Download playlist starting from certain video:
    yt-dlp --playlist-start 5 example.com/watch?v=id&list=listid
    
    # Simulate download:
    yt-dlp -s URL
    
    # List Formats:
    yt-dlp --list-formats URL
    
    # Download preferred format get list of formats & use -f flag:
    yt-dlp -f 18 URL
    
    # Download a list:
    - create a file and place all the YouTube links that you wish to download
    yt-dlp -a youtube_links.txt
    
    # download entire channel (-i to keep going for video's that fail)
    yt-dlp -i https://youtube.com/[channel]

Sphinx
---------------

.. code-block:: shell

    # First time, above the source file
    sphinx-build -M html source/ build/
    
    # Using the Makefile created after the first time
    make html