ISO 9660
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The size of a file is limited to 4GB (2GB in some implementations). This is irrelevant with respect to CD-ROMs, because of their small capacity, but it is a reason to avoid using ISO 9660 on [[DVD-ROM|DVD-ROMs]] and other media. (An extension called "multiple extents" makes larger files possible, but support for it is limited.) | The size of a file is limited to 4GB (2GB in some implementations). This is irrelevant with respect to CD-ROMs, because of their small capacity, but it is a reason to avoid using ISO 9660 on [[DVD-ROM|DVD-ROMs]] and other media. (An extension called "multiple extents" makes larger files possible, but support for it is limited.) | ||
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+ | == Identification == | ||
+ | Usually, the ASCII string "<code>CD001</code>" appears at offset 32769. | ||
+ | |||
+ | The first 32768 bytes are not used. Be aware that hybrid filesystems are possible. Just because something is a valid ISO 9660 filesystem doesn't mean it can't also be a valid filesystem of some other type. | ||
== See also == | == See also == |
Revision as of 01:18, 13 December 2013
ISO 9660 is a read-only filesystem often used on CD-ROMs. It is also common to encounter files containing an image of an ISO 9660 filesystem.
Contents |
Details
The standard limits filenames to the DOS 8.3 style. Several extensions – TRANS.TBL, Rock Ridge, and Joliet – were developed to remove this restriction.
The size of a file is limited to 4GB (2GB in some implementations). This is irrelevant with respect to CD-ROMs, because of their small capacity, but it is a reason to avoid using ISO 9660 on DVD-ROMs and other media. (An extension called "multiple extents" makes larger files possible, but support for it is limited.)
Identification
Usually, the ASCII string "CD001
" appears at offset 32769.
The first 32768 bytes are not used. Be aware that hybrid filesystems are possible. Just because something is a valid ISO 9660 filesystem doesn't mean it can't also be a valid filesystem of some other type.
See also
Software
Reading
Operating systems often include drivers for ISO 9660. On Linux, an ISO 9660 image file can be mounted using a loopback driver (mount -t iso9660 -o loop ...
).
Writing
- cdrkit → genisoimage
- Countless CD burning applications