how to access Macbook Pro hard drive after network boot (OptCmd-R)
Based on this question

NOTE: I am assuming you are in recovery already.

Commands are like this.


Open Terminal from the menu bar (under Utilities)
Change directory: cd /Volumes
List all volumes: ls
Change to the volume you want to access. For example, usually the Mac disk is called "Macintosh HD". So, you would do, cd "Macintosh HD". Replace "Macintosh HD" with the name of your drive
At this point, you can see all files like you would normally.