• For H.264:-

  ffmpeg -i input -c:v libx264 -preset veryslow -crf 0 out.mp4

• For H.265:-

  ffmpeg -i input -c:v libx265 -preset veryslow -x265-params lossless=1 out.mp4

• For WEBM:-

  ffmpeg -i input.mp4 -c:v libvpx-vp9 -lossless 1 out.webm

• For AV1 (experimental):-

  ffmpeg -i input.mp4 -c:v libaom-av1 -crf 0 -b:v 0 -strict experimental av1_test.mkv

  CRF value is from 0 to 63.
  Quoted from the Wiki:

  "Lower values mean better quality and greater file size."

• Left-to-Right:

  convert +append -background black image1.jpg image2.jpg output.jpg

• Top-to-Bottom:

  convert -append -background black image1.jpg image2.jpg output.jpg

• EXAMPLE of merging photos with borders and centered position:-

  convert +append -background black -border 1 -bordercolor white -gravity center image1.jpg image2.jpg output.jpg

1. First of all, convert a .txt file to .ps with ^[5] enscript by running the following command:-

   enscript -p output.ps input.txt

2. And then convert the .ps file to .pdf with ^[6] GhostScript:-

   ps2pdf output.ps output.pdf

• Connect to A Different Network
  
  To disconnect from current connection and connect to a different network, disconnect properly by:
  
  1. Setting the wireless device down first:

     sudo ip link set dev wlp2s0 down

  2. Releasing dhcpcd (otherwise, the initial DHCP client daemon lease will keep running in background. As such, we will encounter an error when connecting to a different network):

     sudo dhcpcd -k wlp2s0

  3. Totally kill the wpa_supplicant process (this step is important to prevent any issues later):

     sudo killall wpa_supplicant

  4. Setting the device up again:

     sudo ip link set dev wlp2s0 up

  5. Connecting to a different network by running wpa_supplicant command with the path to the new network config file:

     sudo wpa_supplicant -B -i wlp2s0 -c /etc/wpa_supplicant/wpa_supplicant.conf

  6. And lastly, restarting dhcpcd:

     sudo dhcpcd wlp2s0

  Provided below is an example of a valid wpa_supplicant.conf file:-

  ctrl_interface=/var/run/wpa_supplicant
  ctrl_interface_group=wheel
  update_config=1
  fast_reauth=1
  ap_scan=1
  
  network={
      ssid="MYSSID"
      psk=59e0d07fa4c7741797a4e394f38a5c321e3bed51d54ad5fcbd3f84bc7415d73d
  }

• Reconnect to The Same Network
  
  If there is a need to disconnect from current connection and later we need to reconnect to the same network, just run the below commands:
  
  
  1. Disconnect:

     sudo ip link set dev wlp2s0 down

  2. Reconnect:

     sudo ip link set dev wlp2s0 up

  Since DHCP client daemon lease has been running in background and we are reconnecting to the same network, there is no need to release / restart dhcpcd.

Rujukan: dhcpcd from archwiki

As I decided to have Vim back as the default editor, some things need to be done in order for synctex search to work.

• open .tex file with the below command:-

  vim --servername VIM

• OR place this line in .zshrc file:-

  alias vim="vim --servername VIM"

• Also, to make it work when opening .tex files from ranger, add this line to the .config/ranger/rifle.conf file:-

  ext tex, has vim = vim --servername VIM "$@"

Rujukan: Synctex with Zathura (linux, easy)

1. Jana kekunci SSH seperti contoh di bawah:-
   - untuk repositori
   git@github.com:saya/blog.git:

   ssh-keygen -f ~/.ssh/id_rsa.blog

   DAN
   - untuk repositori
   git@github.com:saya/saya.github.io.git (web):

   ssh-keygen -f ~/.ssh/id_rsa.web

2. Daripada kekunci SSH yang telah dicipta di atas, buat satu fail konfigurasi yang disimpan sebagai ~/.ssh/config dan mengandungi butiran-butiran seperti berikut:-

   # account for the blog repo on github
   Host github.com-blog
       HostName github.com
       User saya
       IdentitiesOnly yes
       IdentityFile ~/.ssh/id_rsa.blog
   
   # account for the web repo on github
   Host github.com-web
       HostName github.com
       User saya
       IdentitiesOnly yes
       IdentityFile ~/.ssh/id_rsa.web

3. Sunting parameter URL di bahagian [remote "origin"] yang terkandung di dalam fail tempatan .git/config, sebagai contoh daripada tetapan di atas:-

   url = git@github.com-blog:saya/blog.git

   url = git@github.com-web:saya/saya.github.io.git

   Beri perhatian kepada alias hos nama -blog dan -web yang ada pada fail ~/.ssh/config serta .git/config. Lihat juga pada bahagian IdentitiesOnly yes yang terkandung di dalam fail ~/.ssh/config. Baris ini adalah amat penting dalam memastikan bahawa SSH benar-benar menggunakan Fail Identiti seperti yang telah dinyatakan mengikut bahagian masing-masing.

Rujukan: Using Multiple SSH Keys with Github

• commands.py

  class empty(Command):
      """:empty
  
      Empties the trash directory ~/.Trash
          """
  
      def execute(self):
          self.fm.run("sudo rm -rf /home/raihan/.Trash/.*")
          self.fm.run("sudo rm -rf /home/raihan/.Trash/*")

• rc.conf

  map DD shell mv -t /home/raihan/.Trash %s

• rifle.conf

  #-------------------------------------------
  # Personal Settings
  #-------------------------------------------
  #ext mp4|mpeg|avi|flv,       has mpv,      X, flag f = mpv --fs -- "$@"
  ext mp4|mpeg|avi|flv,       has mpv,      X, flag f = mpv -- "$@"
  ext 7z|ace|ar|arc|bz2?|cab|cpio|cpt|deb|dgc|dmg|gz,  has 7z = 7z x -oarchives -- "$@"
  ext iso|jar|msi|pkg|rar|shar|tar|tgz|xar|xpi|xz|zip, has 7z = 7z x -oarchives -- "$@"
  #ext x?html?, has firefox,        X, flag f = firefox -- "$@"
  ext tex, has vim = vim --servername VIM "$@"

• fcitx
• fcitx-configtool
• fcitx-gtk2
• fcitx-gtk3
• fcitx-mozc (for Japanese input method)
• fcitx-qt5

• To kill a process e.g. cmus, find out the pid number with the following command first:-

  pidof cmus

• And then kill it by running the below command:-

  kill <the-pid-number-obtained-by-the-above-command>

Hamba tambahkan baris-baris di bawah ke dalam fail konfigurasi .vimrc.local (untuk ‘plugin’ vimtex):-

let &rtp  = '~/.vim/bundle/vimtex,' . &rtp
let &rtp .= ',~/.vim/bundle/vimtex/after'

Dan kemudiannya hamba kemas kini fail-fail konfigurasi yang berikut:-

• Fail .vimrc.local
  Baris <let g:vimtex_latexmk_options="-pdf -pdflatex='pdflatex -file-line-error -shell-escape -synctex=1'"> ditukarkan kepada:

  let g:vimtex_latexmk_options="-pdf -pdflatex='xelatex -file-line-error -synctex=1 -interaction=nonstopmode -shell-escape %S %O -verbose'"

• Fail .latexmkrc
  Baris <$pdflatex = 'pdflatex -file-line-error -synctex=1 -interaction=nonstopmode -shell-escape %O %S';> digantikan kepada:

  $pdflatex = 'xelatex -file-line-error -synctex=1 -interaction=nonstopmode -shell-escape %S %O -verbose';

1. Suntingan pada fail hijri.py dari pakej ummalqura:-

   #id = mcjdn - UmalqurraArray.ummalqura_dat[index - 1] + 1   # komen baris asal
   id = mcjdn - UmalqurraArray.ummalqura_dat[index - 1] + 0    # tambah baris baru

2. Suntingan pada fail moment-hijri.js:-

   //hd = mjdn - ummalqura.ummalquraData[i - 1] + 1    # komen baris asal
   hd = mjdn - ummalqura.ummalquraData[i - 1] + 0      # tambah baris baru

git submodule add -b master git@github.com-web:saya/saya.github.io.git public

Cloning into '$HOME/hugo/blog/public'...
Enter passphrase for key '$HOME/.ssh/id_rsa.web': 
warning: You appear to have cloned an empty repository.
fatal: 'origin/master' is not a commit and a branch 'master' cannot be created from it
Unable to checkout submodule 'public'

Jadi saya berjaya selesaikan masalah ini melalui pembacaan di [halaman ini].

Langkah-langkah yang perlu dibuat adalah:-

1. Periksa sekiranya origin ada ditetapkan dengan menjalankan baris perintah seperti di bawah:-

   git remote -v

   Jika tiada apa-apa input yang keluar, tinggalkan langkah kedua dan teruskan dengan langkah ketiga diikuti langkah-langkah berikutnya.
   Jika mendapat keputusan seperti ini,

   origin	git@github.com-blog:saya/blog.git (fetch)
   origin	git@github.com-blog:saya/blog.git (push)

   teruskan dengan langkah kedua sehingga akhir.
2. Singkirkan tetapan remote yang lama dengan baris perintah berikut:-

   git remote remove origin

3. Kemudian bolehlah menambah remote yang betul dengan:-

   git remote add origin git@github.com-blog:saya/blog.git

4. Dan akhir sekali, tambahkan submodule:-

   git submodule add -b master git@github.com-web:saya/saya.github.io.git public

   Maklum balas yang sepatutnya diterima adalah seperti ini:-

   Adding existing repo at 'public' to the index

1. nftables to replace iptables.
2. Manual Rujukan Bash: Binaan-binaan Bersyarat > case
3. Manual Rujukan Bash: Fungsi-fungsi Shell