filesystems(4) filesystems(4) NAME filesystems: cdfs, dos, fat, EFS, hfs, mac, iso9660, cd-rom, kfs, nfs, XFS, rockridge, lofs, udf - IRIX filesystem types DESCRIPTION IRIX supports a number of different filesystems. Some of these types are names that can be used with the mount(1) command's -t option. Others are just common names and cannot be used with the mount command. An example of this is the RockRidge type, which is a superset of the iso9660 filesystem type. Therefore RockRidge filesystems are mounted with a command similar to this: mount -t iso9660 -o ro /dev/rdsk/dks0d3vol /CDROM The following filesystem types are supported: bds Not a file system type, an extension to NFS for bulk data transfers. The BDSpro server is an optional product and must be purchased separately. cdfs (CD-ROM) Same as type iso9660 (see below); this is the ABI compliant name. dos (fat) The filesystem used by many personal computers. Types 1, 4, and 6 are supported, included long names where supported. Type 5 (extended partitions) are supported only if mounted with the partition # options. IRIX support for dos filesystems is restricted to removable disk devices such as floppy and floptical disks. Filenames on dos filesystems are restricted to up to an eight character name followed by an optional period and three character filename extension, for most types. Longer names are supported to a limited degree, on the types where the native OS supports them. EFS The older extent-based disk filesystem used by IRIX for disks and also for IRIX software distribution CD-ROMs. See efs(4) for more details. fd A filesystem used to access process file descriptors. hfs (mac) The filesystem used by Macintosh computers. IRIX support for hfs filesystems is restricted to removable disk devices such as floppy and floptical disks and to CD-ROMs. A hfs file is composed of three portions: a data fork, a resource fork, and a desktop information entry. The data fork appears in a normal directory. The resource fork in a special directory (.HSResource) in the file's directory. The desktop information for all files in a directory is contained in the special file .HSancillary. iso9660 (CD-ROM) A CD-ROM filesystem type conforming to ISO standard 9660. iso9660 CD-ROMs are used when the contents of the CD-ROM is intended to be readable by a variety of operating systems. You must install the optional subsystem eoe.sw.cdrom to be able to mount and read an iso9660 CD-ROM. Also see RockRidge below. Note that IRIX software distribution CD-ROMs are not iso9660 filesystems, they are efs filesystems. Music CDs are not file structured and are not used as filesystems. Music CDs can be played using the CD-ROM drive using cdman(1) or cdplayer(1). kfs A network filesystem used to access disks on located on remote computers using AppleShare networking. Generally, AppleShare networking is used to access Macintosh computers. Except for the disk location, kfs filesystems are identical to hfs filesystems. nfs A network filesystem used to access disks located on remote computers. Both NFS Version 2, and NFS Version 3 are supported. In Irix 6.5.24 and beyond, direct I/O is available for NFS Version 3. The subsystem nfs.sw.nfs must be installed to use NFS. proc A filesystem that provides access to the image of each active process in the system. hwgfs A filesystem that provides access to the system hardware configuration. RockRidge A filesystem layered on type of the iso9660 filesystem type (see above) that provides semantics closer to those of standard UNIX filesystems. In particular, it supplies file permissions and allows for directory hierarchies more than 8 levels deep. XFS The next-generation 64-bit high performance journaling filesystem used by IRIX for disks. See xfs(4) for more details. cachefs A caching filesystem for use with efs, xfs, nfs, nfs3, iso9660, hfs, dos, kfs, and cdfs. See cachefs(4) for details. lofs The loopback filesystem allows new virtual filesystems to be created to provide access to existing files using alternative pathnames. The most common use of lofs is by autofs to mount filesystems, exported by the local host. lofs filesystem cannot be mounted using mount(1M) command. After the virtual filesystem is mounted, other filesystems can be mounted within it, covering, but not affecting, parts of the original filesystem. However, filesystems which are subsequently mounted onto the original underlying file system are visible to the virtual file system, except that recursive traversals are not allowed, i.e if / is mounted on /newroot, access to /newroot/newroot would not lead to another filesystems, rather it will appear as a normal directory, just as it was on the original underlying filesystem before the mount. UDF A filesystem type typically used for DVDs. The subsystem eoe.sw.udf must be installed to use UDF. NOTE The nfs and kfs filesystems are optional products. Support for iso9660 filesystems is in the optional subsystem eoe.sw.cdrom. IRIX implements dos, hfs, iso9660, and kfs filesystems as user mode NFS daemons. In some cases errors detected by these daemons are reported as NFS errors. Although NFS is a product option, support for these filesystem types is not dependent on the installation of NFS. Prior to IRIX 6.5.28 the iso9660 filesystem was based on NFS Version 2 and was limited to a maximum accessible filesystem size and file size of 2 GiB. Starting from IRIX 6.5.28 iso9660 can support NFS version 3 protocol which could be used to access larger filesystems and files. Users of IRIX 6.5.27 and earlier releases can use freeware tools such as isoinfo(8) from fw_cdrtools to extract files which are past the 2GiB boundary. SEE ALSO exportfs(1M), fpck(1M), fsck(1M), mediad(1M), mkfp(1M), mkfs(1M), mount(1M), mount_kfs(1M), efs(4), fd(4), fstab(4), hwgfs(4), proc(4), xfs(4). Page 3