How to copy files / folders off a Mac from the command line (optionally using Single User Mode)

mac-file-transfer-via-command-line.md

Mac File Transfer via Single User Mode / Command Line

• Start in Single User Mode by holding down Command-S when starting the Mac.
• Commands can also be typed via Terminal app when OS X is running.

See also: https://support.apple.com/en-us/HT201573
More tips: http://www.tekrevue.com/tip/mac-startup-options/

Terminal Command Workflow

1. Type diskutil list to view available drives
2. Type diskutil mount /dev/disk1s2 (Disk 1, Partition Scheme 2 - may be different on your Mac) to gain read/write access on that disk.
3. Type cd /Volumes to switch current folder to Volumes where Mac OS lists all mounted drives.
4. Type ls to list contents of Volumes folder.
5. Type mkdir to create a new folder (on the USB drive)
6. The cp -a command copies files/folders from one path to another.

Walkthrough

Start in Single-User Mode by holding Command-S as mentioned above You type -> diskutil list

/dev/disk0 (Physical Disk #1: Macintosh HD)

TYPE  NAME  SIZE  IDENTIFIER
0: GUID_partition_scheme *121.3 GB disk0
1: EFI 209.7 MB disk0s1
2: Apple_HFS Macintosh HD 120.5 GB disk0s2
3: Apple_Boot Recovery HD 650.0 MB disk0s3

/dev/disk1 (Physical Disk #2: PIZZA_PIZZA_256GB)

#: TYPE  NAME  SIZE  IDENTIFIER
0: GUID_partition_scheme *256.0 GB disk1
1: EFI 209.7 MB disk1s1
2: Apple_HFS PIZZA_PIZZA_256GB 255.7 GB disk1s

You type -> diskutil mount /dev/disk1s2

Volume PIZZA_PIZZA_256GB on disk1 mounted

You type -> cd /Volumes

/Volumes 13:05:47

You type -> ls

Macintosh HD            PIZZA_PIZZA_256GB                 Recovery Disk Assistant

You type -> cd /Volumes/PIZZA_PIZZA_256GB
You type -> mkdir RecoveredFiles
You type -> cd RecoveredFiles
You type -> cp -a ~/Photos Photos

/Volumes/PIZZA_PIZZA_256GB/RecoveredFiles 13:07:20

Which should copy the entire Mac Photos folder to /Volumes/PIZZA_PIZZA_256GB/RecoveredFiles/Photos

1. An empty line after running the cp command indicates success
2. Copy folder and contained files together using cp -a /Source/FolderName /Destination/FolderName
3. Copy single files without the -a using cp /Source/file.jpg /Destination/file.jpg
4. ~/Photos is the same as /Users/alex/Photos

More copying examples

You type -> cp ~/Photos/myphoto.jpg Photos/myphoto.jpg
You type -> cp -a ~/Documents /Volumes/PIZZA_PIZZA_256GB/RecoveredFiles/Documents
You type -> cp -a ~/Desktop /Volumes/PIZZA_PIZZA_256GB/RecoveredFiles/Desktop

Exit Single User Mode

You type -> reboot

Mac will reboot normally

This is great to know! Thanks!
I need to backup a Mac that failed to update from the terminal in Recovery mode (cmd+R) and now I know how to do it!

Thank you so much!
It would save me my Mini.

thank you! works fine even in 2021