Linux Commands

df says your disk is 80% full, but du says you’re barely using half, so one of them is lying,

You’ve been copying files with cp for years, and if you’re moving a 50GB backup or syncing a directory tree

You need a 1GB test file to benchmark your disk, fill a partition to a specific threshold, or simulate a

You deleted a log file mid-session, a running process is still writing to it, and ls shows nothing, but the

You’re running df -h every 30 seconds by hand to watch a disk fill up, typing the same command over

You’ve been running a long rsync job or a Python script on a remote server only to watch it die

Every Linux user eventually runs a command they’d rather not preserve – a curl with a hardcoded password, an export

Ctrl+R and fc let you find, recall, and edit any command from your bash history in seconds, and here’s how

You’ve been retyping the same long commands for years, but sudo !!, !$, ^old^new, and a handful of Bash history

hyperfine is a command-line benchmarking tool that runs your commands repeatedly, collects timing data across multiple runs, and gives you

Learn how to use systemctl with the –failed flag to instantly spot broken services on your Linux system, without scrolling

The mktemp command in Linux creates temporary files and directories with unique, unpredictable names, which is the safest way to