TRANS.TBL
Encyclopedia
TRANS.TBL is a file on ISO 9660
(Compact Disc
computer data) filesystems, used to provide more flexible filename
s than the basic ones allowed by the ISO 9660 standard. It was the most common way of providing "long filenames" on early computer CDs before the Rock Ridge and Joliet
extensions became widespread.
Strictly created ISO 9660 filenames can only contain up to 8 capital letters or digits, followed by a period and up to three more capital letters or digits. TRANS.TBL is simply a normal file in each directory, containing the extended versions of file names in that directory; a system reading the filesystem can then use the extended filenames (sometimes called "long filenames") instead of the ISO ones.
The TRANS.TBL file is a plain ASCII
text file. Each line contains three fields, separated by an arbitrary amount of whitespace:
Most implementations that create TRANS.TBL files put a single space between the file type and ISO 9660 name and some arbitrary number of tabs between the ISO 9660 filename and the extended filename.
Native support for using TRANS.TBL still exists in many ISO 9660
implementations, particularly those related to Unix
. However, TRANS.TBL has long since been superseded by the Rock Ridge and Joliet
extensions to ISO 9660, and modern utilities that create ISO 9660
images either can't create TRANS.TBL files at all, or no longer create them unless explicitly requested by the user. Since a TRANS.TBL file has no special identification other than its name, it can also be created separately and included in the directory before filesystem creation.
of a CentOS
installation CD, showing the ISO 9660 and extended versions of each filename:
ISO 9660
ISO 9660, also referred to as CDFS by some hardware and software providers, is a file system standard published by the International Organization for Standardization for optical disc media....
(Compact Disc
Compact Disc
The Compact Disc is an optical disc used to store digital data. It was originally developed to store and playback sound recordings exclusively, but later expanded to encompass data storage , write-once audio and data storage , rewritable media , Video Compact Discs , Super Video Compact Discs ,...
computer data) filesystems, used to provide more flexible filename
Filename
The filename is metadata about a file; a string used to uniquely identify a file stored on the file system. Different file systems impose different restrictions on length and allowed characters on filenames.A filename includes one or more of these components:...
s than the basic ones allowed by the ISO 9660 standard. It was the most common way of providing "long filenames" on early computer CDs before the Rock Ridge and Joliet
Joliet (file system)
Joliet is the name of an extension to the ISO 9660 file system. It has been specified and endorsed by Microsoft and has been supported by all versions of its Windows OS since Windows 95 and Windows NT...
extensions became widespread.
Strictly created ISO 9660 filenames can only contain up to 8 capital letters or digits, followed by a period and up to three more capital letters or digits. TRANS.TBL is simply a normal file in each directory, containing the extended versions of file names in that directory; a system reading the filesystem can then use the extended filenames (sometimes called "long filenames") instead of the ISO ones.
The TRANS.TBL file is a plain ASCII
ASCII
The American Standard Code for Information Interchange is a character-encoding scheme based on the ordering of the English alphabet. ASCII codes represent text in computers, communications equipment, and other devices that use text...
text file. Each line contains three fields, separated by an arbitrary amount of whitespace:
- the file type ("F" for file or "D" for directory);
- the ISO 9660 filename (including the usually-hidden ";1" for files); and
- the extended filename, which may contain spaces.
Most implementations that create TRANS.TBL files put a single space between the file type and ISO 9660 name and some arbitrary number of tabs between the ISO 9660 filename and the extended filename.
Native support for using TRANS.TBL still exists in many ISO 9660
ISO 9660
ISO 9660, also referred to as CDFS by some hardware and software providers, is a file system standard published by the International Organization for Standardization for optical disc media....
implementations, particularly those related to Unix
Unix
Unix is a multitasking, multi-user computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas McIlroy, and Joe Ossanna...
. However, TRANS.TBL has long since been superseded by the Rock Ridge and Joliet
Joliet (file system)
Joliet is the name of an extension to the ISO 9660 file system. It has been specified and endorsed by Microsoft and has been supported by all versions of its Windows OS since Windows 95 and Windows NT...
extensions to ISO 9660, and modern utilities that create ISO 9660
ISO 9660
ISO 9660, also referred to as CDFS by some hardware and software providers, is a file system standard published by the International Organization for Standardization for optical disc media....
images either can't create TRANS.TBL files at all, or no longer create them unless explicitly requested by the user. Since a TRANS.TBL file has no special identification other than its name, it can also be created separately and included in the directory before filesystem creation.
Example
A modified version of the TRANS.TBL file in the root directoryRoot directory
In computer file systems, the root directory is the first or top-most directory in a hierarchy. It can be likened to the root of a tree — the starting point where all branches originate.-Metaphor:...
of a CentOS
CentOS
CentOS is a free operating system based on Red Hat Enterprise Linux . It exists to provide a free enterprise class computing platform and strives to maintain 100% binary compatibility with its upstream distribution...
installation CD, showing the ISO 9660 and extended versions of each filename:
D CENTOS CentOS
F GENERIC.INS;1 generic.ins
F GPL.;1 GPL
D HEADERS headers
D IMAGES images
F RELEASE_.;1 RELEASE-NOTES
D REPODATA repodata
F RPM_G000.;1 RPM-GPG-KEY-centos4
F RPM_GPG_.;1 RPM-GPG-KEY
D SRPMS SRPMS
F YUMGROUP.XML;1 yumgroups.xml
F _DISCINF.;1 .discinfo