Miscellaneous notes

Mostly unnecessary for OS X 10.15.3.

What are Extended Attributes (EA) on a file or directory?


xattr <file>

What ACLs are on a file or directory?


ls -le <file>
chmod -RN <dir>

Disconnect USB drive outside of UI

sudo diskutil eject /dev/disk3

Delete Timemachine protected files

/System/Library/Extensions/TMSafetyNet.kext/Contents/Helpers/bypass <rm ...>

Missing Finder shortcuts

ps -ef | grep sharedfilelistd
sudo kill -9 <pid>
option-right-click Finder and select Relaunch

High CPU load

CPU load:

launchctl stop com.apple.pluginkit.pkd && launchctl start com.apple.pluginkit.pkd

Cannot umount volume

sudo lsof | grep /Volumes/ADATA
sudo killall mds
mdutil -i off /Volumes/VolumeName

NTP timekeeping

sudo ntpdate -u time.apple.com

Spotlight enable/disable

Completely disable and reenable:

sudo mdutil -i off /
sudo mdutil -E /
sudo mdutil -i on /


sudo mdutil -sv /

dyld library load error

dyld: Library not loaded: /usr/local/opt/jpeg/lib/libjpeg.9.dylib
  Referenced from: /usr/local/bin/exiftran
  Reason: image not found
fish: 'exiftran' terminated by signal SIGTRAP (Trace or breakpoint trap)


* brew reinstall --build-from-source <package>

Firewall (PF)

If the firewall is enabled, it is not possible to allow/deny by IP range. The links below describe how to setup rules using PF:

  • https://pleiades.ucsc.edu/hyades/PF_on_Mac_OS_X
  • https://www.wavether.com/2016/11/pf-firewall-macos-jetbrains

WiFi bizarre, intermittent latency issues

Disable WiFi. open /Library/Preferences/SystemConfiguration/ Delete these files, then restart:

com.apple.airport.preferences.plist com.apple.network.eapolclient.configuration.plist com.apple.wifi.message-tracer.plist NetworkInterfaces.plist preferences.plist

Confirm with

sudo ping -i 0.1

Safely unmount a USB drive (Fedora)

udisksctl power-off -b /dev/sdb

Ensure WiFi works with new akmods approach (Fedora 25+)

sudo dnf install -y https://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-25.noarch.rpm https://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-25.noarch.rpm
sudo dnf install -y broadcom-wl kernel-devel
sudo akmods --force --kernel `uname -r` --akmod wl
sudo modprobe -a wl
Written on December 30, 2019