Take the 2-minute tour ×
Ask Ubuntu is a question and answer site for Ubuntu users and developers. It's 100% free, no registration required.

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!

share|improve this question
add comment

2 Answers 2

up vote 7 down vote accepted

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.

share|improve this answer
add comment

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.

share|improve this answer
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.