Bash Scripting

List of Shells

• POSIX Shell (sh)
• Bourne Again Shell (bash)
• zsh

Ref:

• https://www.digitalocean.com/community/tutorials/different-types-of-shells-in-linux
• https://www.freecodecamp.org/news/linux-shells-explained/
• https://www.geeksforgeeks.org/different-shells-in-linux/
• https://www.ubuntupit.com/linux-shell-roundup-15-most-popular-open-source-linux-shells/

GNU Bash Reference Manual

• https://www.gnu.org/software/bash/manual/html_node/index.html
• https://tldp.org/LDP/abs/html/index.html
• https://github.com/koalaman/shellcheck/wiki/SC2002

bash variable

Process substitution Command Substitution

(command is subshel ) ... variable with export to be here ...

bashrc file ... bash history ...

Input redirection ... https://www.gnu.org/software/bash/manual/html_node/Redirections.html#Redirecting-Input Output redirection .. https://www.gnu.org/software/bash/manual/html_node/Redirections.html#Redirecting-Output

Here String ... https://www.gnu.org/software/bash/manual/html_node/Redirections.html#Here-Strings

bash builtin commands ... https://www.gnu.org/software/bash/manual/html_node/Bash-Builtins.html https://www.gnu.org/software/bash/manual/html_node/Bourne-Shell-Builtins.html

Double Quote vs Single Quote

Unlimited bash history

https://stackoverflow.com/questions/9457233/unlimited-bash-history