1.1 Bash Cheat Sheet

Bash

File and Folder Navigation

• pwd: Print the current working directory.
• ls: List files and directories in the current directory.
• ls -l: Detailed list with file permissions and sizes.
• ls -a: Show hidden files.
• cd: Change directory.
• cd ..: Move up one directory.
• cd ~: Navigate to the home directory.
• cd /path/to/directory: Navigate to a directory using absolute path.
• cd path/to/directory: Navigate to a directory using relative path.
• mkdir directoryname: Create a new directory.

Viewing and Editing Files with Vim

• vim <filename>: Open a file in the Vim text editor.
• Press i to enter insert mode (for editing).
• Press Esc to exit insert mode.
• To save changes and exit: :wq while not in insert mode.
• To exit without saving: :q! while not in insert mode.

File Permissions (chmod)

• chmod permissions filename: Change file permissions.
• Example: chmod +x script.sh makes a script executable.

Environment Variables

• echo $VARIABLE: Display the value of an environment variable.
• export VARIABLE=value: Set an environment variable.
• unset VARIABLE: Remove an environment variable.

.bashrc (Bash Run Commands)

• .bashrc is a script executed every time you start a new Bash session (i.e. a new terminal tab).
• Useful to run scripts that set environment variables for new terminals.

Searching with grep and Piping

• grep pattern filename: Search for a regex pattern in a file.
• Example: grep "error" log.txt searches for "error" in log.txt.
• Piping (|): Send the output of one command as input to another.
• Example: ls | grep "file" only lists files containing "file" in their names.

Wildcards (for pattern matching)

• *: Matches any characters (e.g., *.txt matches all .txt files).
• ?: Matches a single character.