Debugging Log

Appearance

MacOS Commands ​

  • This document is a complication of commands and technical notes regarding MacOS

Outline ​

Terminal: List only directories for the current location ​

  • ls -d */

scp command notes & examples ​

What is Secure Copy (scp)? ​

  • scp command allows for local ↔️ remote file transfers
  • It uses ssh for data transfer and provides the same authentication and same level of security as ssh.
  • ⚡️ Remember to install scp on local & remote machines!
  • yum install openssh-clients
  • ⚠️ Error: -bash: scp: command not found
  • Solution: Install openssh-clients on your remote & local machine!

Examples Environment ​

  • The examples will use the following environment:
  • Remote host:
    • username: root
    • hostname: 10.224.156.228
  • Local host:
    • username: student
    • File location: ~/Download (it is the same as /Users/student/Download)

Remote to Local ​

  • Copy "demo.txt" from a Remote host to the Local host
    • scp root@10.224.156.228:demo.txt ~/Download
  • Copy multiple files from the remote host to your current directory on the local host
    • scp root@10.224.156.228:/root/\{a,b,c\} .
    • scp root@10.224.156.228:~/\{foo.txt,bar.txt\} .

Local to Remote ​

  • Copy "demo.txt" from the local host to a remote host
    • cd ~/Download | Assumes "demo.txt" is in the Download folder
    • scp demo.txt root@10.224.156.228:/root
  • Copy the directory "AAA" from the local host to a remote host's directory "BBB"
    • scp -r AAA root@10.224.156.228:/root/BBB
  • Copying "foo.txt" & "bar.txt" from the local host to the remote host's home directory
    • scp foo.txt bar.txt root@10.224.156.228:~
  • Copy "foobar.txt" from the local host to a remote host using port 2264
    • scp -P 2264 foobar.txt root@10.224.156.228:/root

Remote to Remote ​

  • Remote_1 -> Remote_2 | Copy the file "foobar.txt" from remote host "rh1.edu" to remote host "rh2.edu"
    • scp root@rh1.edu:/root/foobar.txt \ root@rh2.edu:/root/

scp Performance ​

  • By default scp uses the Triple-DES cipher to encrypt the data being sent.
  • Using the Blowfish cipher has been shown to increase speed.
  • This can be done by using option -c blowfish in the command line.
  • scp -c blowfish some_file root@10.224.156.228:~

Error: bash: scp: command not found ​

  • Make sure your remote host has also scp!
  • Remote CentOS 6: yum install openssh-clients

WindowServer process - MacOS system Process/ Command ​

  • WindowServer process deals with all the visual side of the desktop, the Dock bar, Menu bar, etc.
  • This process makes the control between the UI (user interface) what the user sees and the hardware part.
  • All folders and files that are on the Desktop, the consequences of transparency from the Dock to the menu bar is fully managed with WindowServer process.
  • How to Reduce WindowServer CPU and RAM Usage in macOS?

rm command to delete files & folders ​

  • Syntax: rm [options] file ...
  • Options:
    • -f Attempt to remove the files without prompting for confirmation, regardless of the file's permissions.
    • -i Request confirmation before attempting to remove each file.
    • -r Remove the entire file hierarchy rooted in each file argument. (implies the -d Delete folders).

Examples ​

  • Delete .git directory: rm -rf .git
  • Delete all .jpg files in the current folder: rm *.jpg
  • Delete the folder named "temp", and all its contents: rm -R temp
  • Delete a protected folder: sudo rm -r NAME_OF_FOLDER_TO_DELETE
  • Move the file Hunter.txt to the Trash using mv: $ mv Hunter.txt ~/.Trash

Useful Mac Shortcuts ​

ShortcutCommand
Command(⌘) + Shift(⇧) + ?Open the Help menu's search box
Option(⌥) + Command(⌘) + ESCForce quit an app.
Option(⌥) + Command(⌘) + VMove files to the current location.
Command(⌘) + Left Bracket([)Go to the previous folder.
Command(⌘) + Right Bracket(])Go to the next folder.
Command(⌘) + Up Arrow(▲)Open the folder that contains the current folder.
Command(⌘) + Right Arrow(►)Move cursor to the end of the line
Option(⌥) + Right Arrow(►)Move cursor to the next breakpoint in the line

Mac's Keyboard Symbols ​

Modifier keySymbol
Alt / Option⌥
Control⌃
Shift⇧
Backward delete⌫
Forward delete⌦

Calibrate the battery once every few months ​

If your battery is showing signs of shorter run times, calibrate the battery (once every few months).
To calibrate the battery, follow these instructions:

  1. Fully charge your MacBook.
  2. Once fully charged, leave it plugged in for at least another 2 hours.
  3. Remove the MagSafe power adapter, and use your computer until you get the battery level warning message.
  4. Ignore that message and keep running your notebook.
  5. Eventually the machine will go to sleep.
  6. Do NOT plug it in. Instead, let it sleep for at least 5 hours.
  7. After the time has passed, plug it back in, and let it fully charge.
  8. Once fully charged, your battery has been properly calibrated.

Resetting SMC ​

(On Mac notebooks with non-removable battery)

  1. Shut down the computer.
  2. Plug in the MagSafe or USB-C power adapter to a power source and to your computer.
  3. On the built-in keyboard, press the (left side) Shift-Control-Option keys and the power button at the same time.
  4. Release all the keys and the power button at the same time.
  5. Press the power button to turn on the computer.
  6. On MagSafe power adapters, the LED might change states or temporarily turn off when you reset the SMC.