Tool cheatsheet

Bash and Linux 5 Cheatsheet

Everyday shell and Linux commands for files, searching text, permissions, processes and servers.

Files and directories

List files with details — Long listing including hidden files, with sizes you can read.
Create nested directories — Create a folder and any missing parents.
Copy a directory — Copy a folder and everything in it.
Move or rename a file — Move a file, or rename it by giving a new name in the same folder.
Delete a directory — Remove a folder and everything inside it, without prompting.
Create a symbolic link — Make a link to a file or folder.
Page through a file — Scroll a long file. Press q to quit.
Follow a log file — Print new lines as they are added to a file.
Show the first lines — Print the first 20 lines of a file.

Search file contents — Search a folder recursively and show file names and line numbers.
Find files by name — Find files whose name matches a pattern.
Find files changed recently — Find files modified in the last day.
Count lines — Count the lines in a file.
Count duplicate lines — Sort lines and count how often each appears, most common first.
Replace text in a file — Replace every occurrence of a word in place.
Print one column — Print the second whitespace-separated column of each line.
Run a command on a list of files — Pass matching file names to another command.

Create a compressed archive — Pack a folder into a .tar.gz file.
Extract an archive — Unpack a .tar.gz file into the current folder.
List an archive's contents — See what is inside without extracting.
Connect to a server — Open a shell on a remote machine.
Create an SSH key — Generate a modern Ed25519 key pair. The public key is the .pub file.
Copy a file to a server — Copy a local file to a remote folder over SSH.
Sync a folder to a server — Copy only what changed, preserving permissions, with progress.

List processes — Show every running process with its owner and resource use.
Find a process by name — Search the process list for a name.
Stop a process — Ask a process to terminate gracefully using its PID.
Force-kill a process — End a process immediately when it ignores a normal kill.
Find what is using a port — List the process listening on a port.
Check free disk space — Show space on each mounted filesystem in readable units.
Find what is using space — Show the size of each item in the current folder, largest last.
Check memory — Show used and free memory.
Check a service — Show whether a systemd service is running.
Follow a service's logs — Stream the journal for a systemd unit.
Set an environment variable — Make a variable available to programs started from this shell.

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