How to create ISO file from CD/DVD on OS-X / Mac

from terminal:

#drutil status
Vendor Product Rev
HL-DT-ST DVDRW GS21N SA17

Type: CD-ROM Name: /dev/disk1
Sessions: 1 Tracks: 1
Overwritable: 00:00:00 blocks: 0 / 0.00MB / 0.00MiB
Space Free: 00:00:00 blocks: 0 / 0.00MB / 0.00MiB
Space Used: 62:21:33 blocks: 280608 / 574.69MB / 548.06MiB
Writability:


#diskutil unmountDisk disk1

#dd if=/dev/disk1 of=/file_name.iso

#diskutil mountDisk disk1