Useful built-in macOS command-line utilities (weiyen.net)

open -n file.pdf : opens new instance of Preview application which is useful if you want to open the same file twice (for example to look at different pages at once).

caffeinate -d : prevents display turning off, useful if you want to look at display without moving mouse.

Very useful.

/System/Library/PrivateFrameworks/Apple80211.framework/Versions/A/Resources/airport -s

I set a shell alias so I can just do `airport -s`. I've no idea why this is hidden away inside some framework and not in a directory which is in the normal path, but there you go.

     "...a menu driven program which partitions disks using the standard
     Apple disk partitioning scheme described in "Inside Macintosh: Devices".
     It does not support the Intel/DOS partitioning scheme[.]"

Say you've got a directory that has scripts or data files related to some thing you do. For example I've got several scripts that I use when I scan books with my book scanner. I only need these when doing book scanning stuff so don't want to put them somewhere in $PATH. I want to be able to easily run them from scripts that aren't in that directory, but I don't want to hard code the path to that directory.

Solution: in the directory with the book scanning scripts I make a file named ID that contains a unique string. I currently use 16 byte random hex strings [1].

I have this script, named find-dir-by-ID, somewhere in $PATH:

  #!/bin/zsh
  ID=${1:?Must specific ID}
  IDSHA=`echo $ID | shasum | cut -d ' ' -f 1`
  mdfind $ID 2>/dev/null | grep /ID | while read F; do
      FSHA=`shasum $F | cut -d ' ' -f 1`
      if [ $IDSHA = $FSHA ]; then
          dirname $F
          exit 0
      fi
  done
  exit 1

  SCRIPT_DIR=`find-dir-by-ID 54f757919a5ede5961291bec27b15827`
  if [ ! -d $SCRIPT_DIR ]; then
    >&2 echo Cannot find book scanning scripts
    exit 1
  fi

The IDs do not have to be hex strings. If I'd thought about it more I probably would have made IDs look like this "book-scanning:54f757919a5ede59" or "arduino-tools:3b6b4f47bf803663".

[1] here's a script for that:

  #!/bin/sh
  N=${1:-8} # number of bytes
  xxd -g $N -c $N -p -l $N < /dev/urandom

(shift+command+K) or Menu 'Shell' -> 'New Remote Connection...'

opens a SSH, S(FTP), TELNET connection manager window!

For example I'm having a problem that comes and goes now and then where Bluetooth audio is 300 ms delayed compared to the video playback everywhere except in Youtube on Safari, very strange. It's good for a few months then suddenly it becomes unusable, then back to zero sync delay after a few months.

I was thinking this might be related to CODEC selections etc or some hidden setting that might get changed which we normally aren't allowed to determine :)

(btw I know there is a difference between latency and synchronization - latency might be unavoidable but video sync should always be able to compensate - I got curious on how exactly that works, where in the app / SDK / OS pipeline does the a/v sync happen on a Mac?)

To scare your teammates when you are logged in remotely optionally with

$ osascript -e "set volume output volume 100"

/usr/bin/plutil -extract your.key.path raw -o - - <<< "$jsoninput"

(obviously, less useful now that `jq`is built in)

I use it most often for pulling lat lon data from photos.

  upgrade_macos() {
    softwareupdate --list
    softwareupdate --download
    softwareupdate --install --all --restart
  }

    sudo powermetrics

Docs are at https://ss64.com/mac/diskutil.html

   hear (macOS speech recognition and dictation via the command line)

(Uses built-in macOS capabilities for transcription from audio to text.)