Unix Resources

Westwind’s reference page.

Man Pagez or Man Pages

The X-Lab

Elevated Shell Shell as actual root user sudo su. Alternatively, sudo -s gives you elevated permissions but your home is still your home. If you just want to change to an admin user in Terminal type su <admin username>.

flush DNS Cache

Turn off Mail preview of attachments – defaults write com.apple.mail DisableInlineAttachmentViewing -bool yes (or false)

Copy only email address in Mail – defaults write com.apple.mail AddressesIncludeNameOnPasteboard -bool false (or no)

List files in a directory and output the list  to a text file on the hard drive: ls > ~/list-of-files.txt

Disk Usage (this takes a while to run) sudo du -sh /* or df -hT hfs (display free disk space)

MemTest cd /usr/bin, memtest all, CTRL C. Instructions can be found on this page.

Enable Disk Utility’s debug menu  defaults write com.apple.DiskUtility DUDebugMenuEnabled 1  (change 1 to 0 to disable the debug menu)

chflags hidden /FilePath or chflags no hidden or SetFile -a V filename.txt or use a .

Clear font caches and databases: sudo atsutil databases -remove or get FontNuke

Diff lets you compare files or folders, diff file-1 file-2 or diff -rq folder-1 folder-2. Example, diff -rq [path to folder 1] [path to folder 2] > ~/Desktop/comparison.txt

This command will provide a nice list of files that occur in dirA but not in dirB, files that occur in dirB, but not in dirA, and files that differ between dirA and dirB. Pipe the output through grep to remove mention of uninteresting files, and sort to tidy it up, e.g.:
diff -qr dirA dirB | grep -v -e ‘DS_Store’ -e ‘Thumbs’ |
sort > diffs.txt

List of Defaults commands

MacAdmins’ favorites

touch ~/timestamp and then change some setting and then find -x / -newer ~/timestamp >~/changedfiles.txt” to generate a list of changed files, and store it in your home directory under the name “changedfiles.txt”. One of these changed files should be the settings file you need to locate.

Enter date XXXX and press Return  format: [mm][dd][HHMM][yy]

For installers with expired certs use Terminal to change date to 0201010116 This should work for Lion, Mountain Lion and Mavericks, 10.7, 10.8 and 10.9

Make Install Media examples:Apple support article

Remember that it is 2 dashes, not an em dash

sudo /Applications/Install\ macOS\ Mojave.app/Contents/Resources/createinstallmedia –volume /Volumes/14

sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia –volume /Volumes/13

sudo /Applications/Install\ macOS\ Sierra.app/Contents/Resources/createinstallmedia –volume /Volumes/12 –applicationpath /Applications/Install\ macOS\ Sierra.app

sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia –volume /Volumes/MyVolume

sudo /Applications/Install\ OS\ X\ El\ Capitan.app/Contents/Resources/createinstallmedia –volume /Volumes/11 –applicationpath /Applications/Install\ OS\ X\ El\ Capitan.app

sudo /Applications/Install\ OS\ X\ Yosemite.app/Contents/Resources/createinstallmedia –volume /Volumes/10 –applicationpath /Applications/Install\ OS\ X\ Yosemite.app

/createinstallmedia –volume /Volumes/9 –applicationpath /Applications/Install\ OS\ X\ Mavericks.app –nointeraction

Mountain Lion OS X 10.8 http://osxdaily.com/2012/02/17/make-bootable-os-x-10-8-mountain-lion-usb-install-drive/

Lion and Mountain Lion and newer http://www.sallonoroff.co.uk/blog/2015/11/make-a-bootable-usb-drive-with-createinstallmedia/

Leopard and Snow Leopard https://www.macworld.com/article/2023548/dvd-less-snow-leopard-installation-on-older-mac.html

View All Third Party Kernel Extensions kextstat | grep -v com.apple

Unload Kernel Extension sudo kextunload /System/Library/Extensions/ThirdPartyMystery.kext

System Integrity Protection (SIP), aka rootless csrutil enable and csrutil disable

Disable Time Machine local backups: sudo tmutil disablelocal

The application SomeApp.app can’t be opened. Superuser.com Question 898124  chmod +x SomeApp.app/Contents/MacOS/*

Sierra installer payload failed signature check, resolved by checking date and seeing that it was set to the year 2000. Within Terminal I typed ntpdate -u time.apple.com to resolve this issue.

Spotlight commands

Encrypted zip archive zip -ej ~/Desktop/file.zip ~/Desktop/Kitties.JPG

unzip file.zip -d ~/another/folder

Trigger Setup Assistant so you can create a new admin-level account. mount -uw / then rm /var/db/.applesetupdone

rm -rf some_dir r “recursive” -f “force” (suppress confirmation messages)

Disable Gatekeeper sudo spctl –master-disable

defaults write com.apple.DiskUtility DUDebugMenuEnabled 1 and then killall Finder then open Disk Utility, go to the Debug menu and select Show All Partitions

Time Machine tmutil info https://eclecticlight.co/2017/02/16/diagnosing-and-treating-time-machine-problems-in-terminal/

sudo /usr/sbin/softwareupdate –ignore “macOS Catalina”


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