1* 2* Documentation/filesystems/udf.txt 3* 4UDF Filesystem version 0.9.8.1 5 6If you encounter problems with reading UDF discs using this driver, 7please report them to linux_udf@hpesjro.fc.hp.com, which is the 8developer's list. 9 10Write support requires a block driver which supports writing. Currently 11dvd+rw drives and media support true random sector writes, and so a udf 12filesystem on such devices can be directly mounted read/write. CD-RW 13media however, does not support this. Instead the media can be formatted 14for packet mode using the utility cdrwtool, then the pktcdvd driver can 15be bound to the underlying cd device to provide the required buffering 16and read-modify-write cycles to allow the filesystem random sector writes 17while providing the hardware with only full packet writes. While not 18required for dvd+rw media, use of the pktcdvd driver often enhances 19performance due to very poor read-modify-write support supplied internally 20by drive firmware. 21 22------------------------------------------------------------------------------- 23The following mount options are supported: 24 25 gid= Set the default group. 26 umask= Set the default umask. 27 uid= Set the default user. 28 bs= Set the block size. 29 unhide Show otherwise hidden files. 30 undelete Show deleted files in lists. 31 adinicb Embed data in the inode (default) 32 noadinicb Don't embed data in the inode 33 shortad Use short ad's 34 longad Use long ad's (default) 35 nostrict Unset strict conformance 36 iocharset= Set the NLS character set 37 38The uid= and gid= options need a bit more explaining. They will accept a 39decimal numeric value which will be used as the default ID for that mount. 40They will also accept the string "ignore" and "forget". For files on the disk 41that are owned by nobody ( -1 ), they will instead look as if they are owned 42by the default ID. The ignore option causes the default ID to override all 43IDs on the disk, not just -1. The forget option causes all IDs to be written 44to disk as -1, so when the media is later remounted, they will appear to be 45owned by whatever default ID it is mounted with at that time. 46 47For typical desktop use of removable media, you should set the ID to that 48of the interactively logged on user, and also specify both the forget and 49ignore options. This way the interactive user will always see the files 50on the disk as belonging to him. 51 52The remaining are for debugging and disaster recovery: 53 54 novrs Skip volume sequence recognition 55 56The following expect a offset from 0. 57 58 session= Set the CDROM session (default= last session) 59 anchor= Override standard anchor location. (default= 256) 60 volume= Override the VolumeDesc location. (unused) 61 partition= Override the PartitionDesc location. (unused) 62 lastblock= Set the last block of the filesystem/ 63 64The following expect a offset from the partition root. 65 66 fileset= Override the fileset block location. (unused) 67 rootdir= Override the root directory location. (unused) 68 WARNING: overriding the rootdir to a non-directory may 69 yield highly unpredictable results. 70------------------------------------------------------------------------------- 71 72 73For the latest version and toolset see: 74 http://linux-udf.sourceforge.net/ 75 76Documentation on UDF and ECMA 167 is available FREE from: 77 http://www.osta.org/ 78 http://www.ecma-international.org/ 79 80Ben Fennema <bfennema@falcon.csc.calpoly.edu> 81