Nineteen flashcards covering the Linux command line fundamentals every developer and sysadmin should know. Includes navigation and file management commands, the permissions model and chmod/chown, process management, piping and redirection, package managers, an...
Nineteen flashcards covering the Linux command line fundamentals every developer and sysadmin should know. Includes navigation and file management commands, the permissions model and chmod/chown, process management, piping and redirection, package managers, and essential tools like grep, find and ssh. Useful for CompTIA Linux+, coursework and technical interviews.
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Prints the full path of the current working directory.
Lists all files in the current directory, including hidden files (-a), in long format (-l) showing permissions, owner, size and modification date.
cp copies a file or directory; mv moves or renames it; rm deletes it (use -r for directories, -f to force without prompting).
Owner gets read/write/execute (7), group gets read/execute (5), others get read/execute (5) — common for executable scripts.
read (view contents), write (modify contents), execute (run as a program or, for directories, enter/list them).
Changes the owner and group of a file or directory to the specified user and group.
A snapshot of all running processes on the system, including the user, PID, CPU/memory usage and command that started each process.
Sends the SIGKILL signal to immediately and forcibly terminate the process with the given process ID, without allowing it to clean up.
A foreground process occupies the terminal until it finishes. A background process (started with & or moved with bg) runs without blocking the terminal.
> redirects output to a file, overwriting existing content. >> redirects output to a file, appending to existing content.
Searches logfile.txt for lines containing the string "error" and prints matching lines to standard output.
Recursively searches from the root directory for all files whose name ends in .log.
Displays disk space usage for mounted filesystems in a human-readable format (KB/MB/GB rather than raw blocks).
Shows the total ("summarised") disk usage of a directory in human-readable format.
Executes a single command with superuser (root) privileges, requiring the user's own password and logging the action, rather than logging in as root directly.
Debian/Ubuntu: apt (or apt-get). Red Hat/CentOS/Fedora: yum or the newer dnf.
Opens a secure encrypted remote shell session to the specified host, authenticating as the given user (via password or SSH key).
Opens the manual page for a command, showing its usage, options and examples — the built-in reference documentation.
A pointer file referencing another file or directory by path, created with ln -s target linkname. Deleting the link does not delete the target.
