I was wondering what "loop" mean in this usage of mount:
mount -t iso9660 -o loop matlab.iso /media/cdrom0
Is it a type of device? What does this device type "loop" mean? Can I choose other device types for the iso file? Thanks!
A "loop" device in Linux is an abstraction that lets you treat a file like a block device. It's specifically meant for a use like your example, where you can mount a file containing a CD image and interact with the filesystem in it as if it were burned to a CD and placed in your drive.
You can find more information on Wikipedia.
The loop
option to mount (it's not a type, it's an option) tells mount that this is a "loopback" device - a regular file to be used as a block device.
In the background, mount sets up a loopback device (/dev/loopX
), then mounts that at /media/cdrom0.