This project contains useful bash aliases and functions. Bash aliases are essentially shortcuts that save you from having to remember long commands and save you a lot of typing when working on the command line.
To make the alias or function persistent you need to declare it in the ~/.bashrc file. If you want to make your ~/.bashrc more modular, you can store your aliases in a separate file. Some distributions, such as Ubuntu and Debian, include a ~/.bash_aliases file that is referenced in ~/.bashrc.
Pick the shortcuts you are interested in and copy the code into one of the files mentioned above.
Alias definition:
sudo='sudo ' Usage:
sudo <youralias> How it works: If the last character of the alias value is a blank, then the next command word following the alias is also checked for alias expansion. See https://www.gnu.org/savannah-checkouts/gnu/bash/manual/bash.html?ref=linuxhandbook.com#Aliases.
Alias definition:
function mount.iso() { # $1: the iso file if [ $# -eq 1 ]; then sudo mkdir -p /media/iso sudo mount -o loop -t iso9660 "$1" /media/iso else echo Usage: mount.iso \<iso-file\> fi } function umount.iso() { sudo umount /media/iso sudo rmdir /media/iso } Convert MP4 files to MP3 files:
alias convert.mp42mp3='for f in *.mp4; do ffmpeg -i "$f" "${f%.mp4}.mp3"; done' Convert MOV files to MP4 files
alias convert.mov2mp4='for i in *.mov; do ffmpeg -i "$i" -vcodec h264 -crf 30 -acodec aac "${i%.mov}_new.mp4"; done' Convert high quality MP4 files to MP4 files with lower quality:
alias convert.mp42mp4='for i in *.mp4; do ffmpeg -i "$i" -vcodec h264 -crf 30 -acodec aac "${i%.mp4}_new.mp4"; done' Or if the conversion is to be done for individual files:
function convert.mp42mp4.file() { # $1: input file name if [ "$#" == 0 ]; then echo Usage: convert.mp42mp4.file \<file\> [\<file\> ...] return 1 else for n in "$@" do if [ "${n##*.}" == "mp4" ]; then outputFile="${n%.*}"_new.mp4 ffmpeg -i "$n" -vcodec h264 -crf 30 -acodec aac "$outputFile" fi done fi } function download.m3u8 { # $1: m3u8 url # $2: output filename if [ $# -eq 2 ]; then cd ~/Downloads ffmpeg -protocol_whitelist file,http,https,tcp,tls,crypto -i "$1" -c copy "$2" else echo Usage: download.m3u8 \<m3u8-url\> \<output-file\> fi } function mkdir.mp3() { # $1: start index if [ "$#" != 1 ]; then echo Usage: mkdir.mp3 \<start-index\> return 1 else # check input if [ $(($1 % 6)) != 1 ]; then echo Error: Input is not a valid start index return 1 fi lastIndex=$(($1+5)) folder=MP3_$1-$lastIndex for i in $(seq $1 $lastIndex); do mkdir -p $folder/MP3_$i done fi } function tar.encrypt() { # $1...: files or folders to encrypt if [ "$#" == 0 ]; then echo Usage: tar.encrypt \<file\> [\<file\> ...] return 1 else tar czvpf - "$@" | gpg --symmetric --cipher-algo aes256 -o archive.tar.gz.gpg fi } function tar.decrypt() { # $1: archive to decrypt if [ "$#" != 1 ]; then echo Usage: tar.decrypt \<archive\> return 1 else gpg -d $1 | tar xzvf - fi } function grep.findfiles() { # $1: search text # $2: directory if [ "$#" != 2 ]; then echo Usage: grep.findfiles \<search-text\> \<directory\> return 1 else # -R: recursive # -i: ignore case # -l: print the name of the files grep -Ril "$1" "$2" fi } https://www.gnu.org/software/bash/manual/html_node/Shell-Parameter-Expansion.html
${param#pattern} : pattern must match the beginning of param, the rest is returned
${param%pattern} : pattern must match the ending of param, the rest is returned