Commands - osxhub

Terminal readout of the WIFI section from sudo wdutil info on a Mac, with RSSI -32 dBm (strong signal) and SNR 60 dB highlighted, plus Noise -92 dBm, Tx Rate 1200 Mbps, PHY Mode 11ax (Wi-Fi 6), Channel 5g44/80, and Security WPA3 Personal, and a note that it replaces the removed airport -I command

wdutil on Mac: Check Wi-Fi Signal and Diagnose the Connection from the Terminal

by Marcus Reeve
July 21, 2026July 19, 2026

When you want to see how strong your Wi-Fi actually is from the Terminal — signal, noise, channel, the negotiated rate — wdutil is the built-in tool that answers it on current macOS. It replaced…

Two working macOS commands shown in green — netstat -an piped to grep LISTEN to list listening ports, and lsof -i to find the process on a port — above three netstat flags that exit 0 while printing unrelated output

How to List Listening Ports and Find the Process on macOS

by Marcus Reeve
July 17, 2026July 18, 2026

Two questions send most people to netstat on a Mac: which ports are listening, and which process holds one open. On macOS 26.5.2, the first has a one-line answer; the second doesn’t involve netstat at…

How to Clear DNS Cache on macOS: The Command Isn’t the Same on Every Version

by Marcus Reeve
July 1, 2025July 17, 2026

On macOS 26.5.2 (Tahoe, build 25F84), the command that clears DNS-related caches is two commands run back to back: sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder Both binaries exist on this machine at /usr/bin/dscacheutil… Read…

Command reference for macOS softwareupdate: --list to see available updates, --download --all, --install --recommended, and --fetch-full-installer to download a full macOS installer

macOS softwareupdate: Disabling Updates, Fetching Installers

by Marcus Reeve
June 26, 2025July 18, 2026
4 Comments

softwareupdate is how macOS installs its own updates from the Terminal — check what is available, download it, install it, and, where the machine still allows it, hold updates back. The recurring trap is that…

Two-step macOS terminal card: step 1, lsof -i :3000 -P -n finds the process listening on port 3000; step 2, lsof -ti :3000 piped to xargs kill frees the port

lsof on Mac: Find and Kill the Process Using a Port

by Marcus Reeve
June 26, 2025July 18, 2026

lsof lists open files, and on macOS “open file” includes network sockets — so it answers two questions people reach for it constantly: what’s using a port you need, and what’s quietly holding a file…

Dark terminal card headed macOS routing table management, showing three labelled operations: View with netstat -rn, Change with sudo route add -net 10.0.0.0/8 192.168.1.1, and Persist with sudo networksetup -setadditionalroutes Wi-Fi

How to Show and Manage the macOS Routing Table

by Marcus Reeve
June 24, 2025July 21, 2026

Every Mac keeps a routing table: the kernel’s list of where to send each outgoing packet. The system builds it from your network settings, so most of the time you never have to touch it.…

Terminal on macOS 26.5.2 showing three ways to end a process: kill by PID, pkill by command-line pattern, and killall by exact name

How to Kill a Process on macOS: kill, pkill, killall, and launchctl

by Marcus Reeve
June 22, 2025July 18, 2026

Ending a process on macOS is two steps: find it, then send it a signal. ps, pgrep, and lsof find it; kill, pkill, and killall end it. The three “kill” commands differ only in how…

Terminal showing hdiutil convert app.dmg -format UDTO -o app.iso returning a file named app.iso.cdr instead of app.iso, on macOS 26.5.2

The hdiutil Command on macOS: Disk Images, DMG-to-ISO, and the .cdr Gotcha

by Marcus Reeve
June 22, 2025July 18, 2026

hdiutil is the command macOS uses to build, mount, convert, and inspect disk images — .dmg, .sparseimage, .sparsebundle, and the raw .iso/.cdr family. It ships with the system at /usr/bin/hdiutil and talks to Apple’s DiskImages…

The man diskutil addVolume synopsis line, bracket dash group With pipe dash sibling groupDevice, highlighting that -sibling appears 3 times in 2,370 lines and is never explained

macOS diskutil: APFS Volume Groups and the -sibling Flag

by Marcus Reeve
June 22, 2025July 18, 2026
2 Comments

In December 2025 a reader named Maik Kaune left a question on this post that turned out to be sharper than the article it was attached to. He had already worked out how to build…

Dark guide card headed Build a bootable macOS USB, showing the four steps in order: step one pick a version with softwareupdate --list-full-installers, step two verify it by listing the createinstallmedia path inside the installer, step three write the drive with createinstallmedia --volume /Volumes/MyVolume, and step four start from it using the power button on Apple silicon or Option on Intel

How to Create a Bootable macOS USB Installer

by Marcus Reeve
June 21, 2025July 20, 2026

A bootable macOS USB stick lets you install or reinstall macOS on a Mac that will not start normally, set up several machines without downloading the installer each time, or do a clean install rather…