Up to Mac OS X 10.7, physical CD-ROMs can be mounted within SheepShaver. Just insert the CD on the host system and the CD will be mounted on the guest desktop. OS X 10.8 and later prevents mounting of physical CD-ROMs in SheepShaver.
What about physical hard drives and physical USB sticks? Can physical hard drives and physical USB sticks be mounted within SheepShaver on Mac OS X 10.7 or on Linux? (Concerning Linux, I am particularly interested in the Vasi-forked SheepShaver for Linux released on 2019-07-13.)
If they can, I have a further question. Even though hard drives and USB sticks in general are writable, it is possible to write-protect hard drives and USB sticks. Can write-protected physical hard drives and physical USB sticks be mounted within SheepShaver on Mac OS X 10.7 or on Linux?
Note: A device called "ForensicPC Tableau" can write-protect hard drives. Some USB sticks have write-protection tabs. Moreover, all SD cards have write-protection tabs, and a USB-connected SD card reader/writer holding an SD card looks and works like a USB stick.