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macOS terminal showing caffeinate -i ./backup.sh with the note 'awake until it finishes', beside a table of caffeinate -d (keep the display on), -t 3600 (stay awake for one hour), -w PID (until a process ends), and pmset -g assertions (see what's keeping it awake).

How to Prevent Your Mac from Sleeping (caffeinate)

by Marcus Reeve
August 21, 2026July 19, 2026

macOS has a built-in command for keeping your Mac awake — caffeinate — so there’s no app to install. Its most useful trick is wrapping a command so the Mac stays up for exactly as…

macOS terminal showing xcode-select --install, next to two cards comparing the Command Line Tools (git, clang, make; a few hundred MB; what most people need) with full Xcode (the full IDE; 10+ GB from the App Store; only to build and ship apps).

How to Install the Xcode Command Line Tools on macOS

by Marcus Reeve
August 18, 2026July 19, 2026

Most command-line development on a Mac needs only the Xcode Command Line Tools — the compilers, git, and make, a few hundred megabytes — not the full multi-gigabyte Xcode IDE. Here’s how to install just…

Table of GNU-to-BSD command differences on macOS: find -printf becomes find -ls or -exec stat; sed -i needs an empty ''; date -d becomes date -v or -j -f; stat -c becomes stat -f; with a note that brew install coreutils provides gdate, gstat, and greadlink.

Why Your Linux Commands Fail on macOS (BSD vs GNU)

by Marcus Reeve
August 15, 2026July 19, 2026

macOS’s command-line tools come from BSD, not the GNU coreutils that ship with most Linux distributions. They cover the same ground, but their flags don’t always match — so a command copied straight from a…

$Two-column table comparing GNU sed on Linux with BSD sed on macOS: sed -i needs an empty '' argument (sed -i '' 's/.../'); \+ is literal so use -E; \U case conversion is unsupported so install gsed; with a footer noting -i.bak for backups, -E for + ? |, and that \n now works.$

The sed Command on macOS: What’s Different from Linux

by Marcus Reeve
August 12, 2026July 19, 2026

macOS ships BSD sed at /usr/bin/sed, not the GNU version Linux uses. Most substitutions work the same, but a few differences turn a copied-from-Linux command into a cryptic error — and the -i flag is…

Two-column table comparing GNU find on Linux with BSD find on macOS: find -name without a path is illegal on macOS (needs find . -name); -printf gives unknown primary or operator; -regextype is replaced by find -E . -regex; find --version gives illegal option; while -type, -iname, -delete, -maxdepth and -exec + work the same.

The find Command on macOS: What’s Different from Linux

by Marcus Reeve
August 10, 2026July 19, 2026

macOS ships the BSD version of find at /usr/bin/find, not the GNU findutils version most Linux distributions use. Most of what you know carries over unchanged — but a handful of habits from Linux tutorials…

macOS Terminal showing zsh: command not found: gti after a typo, beside a table of the five causes and their one-command fixes: typo (command -v), not installed (brew install), not on PATH (add to ~/.zprofile), just installed (rehash), and local script (./script with chmod +x).

“zsh: command not found” on macOS: Causes and Fixes

by Marcus Reeve
August 7, 2026July 19, 2026

When the Terminal prints zsh: command not found: something, it means zsh looked through every directory on your PATH and didn’t find a program by that name. zsh has been the default shell since Catalina…

Three verified macOS Terminal commands in a table: printf '%s' "user:pw" | base64 gives dXNlcjpwdw==; base64 -d

How to Encode and Decode Base64 on macOS

by Marcus Reeve
August 5, 2026July 19, 2026

macOS ships a base64 command at /usr/bin/base64, so there’s nothing to install — it’s the FreeBSD version, which differs from the GNU one on Linux in a couple of ways worth knowing. This covers encoding…

Homebrew install prefixes on macOS: on Apple Silicon brew --prefix returns /opt/homebrew, on Intel it returns /usr/local, above a row of common verbs install, list, upgrade, cleanup, services, bundle dump.

How to Install and Use Homebrew on macOS

by Marcus Reeve
August 2, 2026July 19, 2026

Homebrew is the package manager most Mac developers use to install command-line tools and apps from the Terminal. This covers installing it, the commands you’ll use day to day, running background services, backing up your…

Two columns comparing a PATH before and after macOS path_helper runs: on the left, /opt/homebrew/bin set in ~/.zprofile sits at position 1 above /usr/bin and /bin; on the right, after /etc/zprofile runs path_helper, /opt/homebrew/bin has moved to position 14, below /usr/bin and /bin.

How to Add to PATH on macOS

by Marcus Reeve
July 31, 2026July 19, 2026

Adding a directory to your PATH is how you get macOS to find a command by name instead of typing its full location every time. There’s more than one way to do it, and which…

Dark card headed Mac DFU mode: revive or restore, comparing two operations: REVIVE reinstalls firmware and keeps your data (try first), and RESTORE erases the drive and installs a clean macOS (fallback), with a note that it runs from Finder on a second Mac running macOS 14 or later over USB-C

How to Put a Mac in DFU Mode (and Revive or Restore It)

by Marcus Reeve
July 30, 2026July 21, 2026

DFU mode is the deepest recovery state on a Mac. DFU stands for Device Firmware Update, and you reach for it in the rare case where a Mac will not turn on, stops at a…