tolerance=9999A Directory Structure for <tex /> FilesTUG Working Group on a Directory Structure (TWGTDS)2GELLMU Edition edited by W.F.HammondUlrik Vieths markup and processing scheme for the 0.995 version of this document helped crystallize the idea for GELLMU in the mind of the editor.This version was reedited technically for Generalized Extensible LaTeXLike MarkUp (GELLMU) on 13Jul2000 Copyright 1994, 95, 96, 97, 98, 99 Users GroupPermission to use, copy, and distribute this document without modification for any purpose and without fee is hereby granted, provided that this notice appears in all copies It is provided as is without expressed or implied warrantyPermission is granted to copy and distribute modified versions of this document under the conditions for verbatim copying, provided that the modifications are clearly marked and the document is not represented as the official oneThis document is available on any CTAN host (Appendixiref="sec:Related-references"sec:Related-references has a complete reference) Please send questions or suggestions by email to tdstug.org or by postal mail to Karl Berry, 135 Center Hill Road, Plymouth, MA 02360, USA We welcome all comments 1IntroductionSU-11.1The role of the TDSSU-1.11.2ConventionsSU-1.22GeneralSU-22.1Subdirectory searchingSU-2.12.2Rooting the treeSU-2.22.3Local additionsSU-2.32.4Duplicate filenamesSU-2.43Toplevel directoriesSU-33.1MacrosSU-3.13.2FontsSU-3.23.3Nonfont MetaFont filesSU-3.33.4MetaPostSU-3.43.5BibTeXSU-3.53.6DocumentationSU-3.63.7ExtensionsSU-3.74SummarySU-44.1Documentation tree summarySU-4.1AppendixAUnspecified piecesSU-5A.1Portable filenamesSU-5.1AppendixBImplementation issuesSU-6B.1Adoption of the TDSSU-6.1B.2More on subdirectory searchingSU-6.2B.3Example implementationspecific treesSU-6.3AppendixCIs there a better way?SU-7C.1Macro structureSU-7.1C.2Font structureSU-7.2C.3Documentation structureSU-7.3AppendixDRelated referencesSU-8AppendixEContributorsSU-9pagebreak
1Introduction is a powerful, flexible typesetting system used by many people around the world It is extremely portable and runs on virtually all operating systems One unfortunate side effect of s flexibility, however, is that there has been no single right way to install it This has resulted in many sites having different installed arrangementsThe primary purpose of this document is to describe a standard Directory Structure (TDS): a directory hierarchy for macros, fonts, and the other implementationindependent system files As a matter of practicality, this document also suggests ways to incorporate the rest of the files into a single structure The TDS has been designed to work on all modern systems In particular, the Technical Working Group (TWG) believes it is usable under MacOS, msdos, os2, Unix, vms, and Windows nt We hope that administrators and developers of both free and commercial implementations will adopt this standardThis document is intended both for the system administrator at a site and for people preparing distributionseverything from a complete runnable system to a single macro or style file It may also help users find their way around systems organized this way It is not a tutorial: we necessarily assume knowledge of the many parts of a working system If you are unfamiliar with any of the programs or file formats we refer to, consult the references in Appendixiref="sec:Related-references"sec:Related-references 1.1The role of the TDSThe role of the TDS is to stabilize the organization of related software packages that are installed and in use, possibly on multiple platforms simultaneouslyAt first glance, it may seem that the Comprehensive Archive Network (CTAN) archives fulfill at least part of this role, but this is not the case The role of CTAN is to simplify archiving and distribution, not installation and useIn fact, the roles of the TDS and CTAN are frequently in conflict, as you will see elsewhere in this document For distribution, many different types of files must be combined into a single unit; for use, it is traditional to segregate files (even similar files) from a single package into separate, occasionally distant, directories 1.2ConventionsIn this document, is used to separate filename components; for example, texmffonts This is the Unix convention but the ideas are in no way UnixspecificIn this document, generally means the system, including MetaFont, DVI drivers, utilities, etc., not just the program itselfThe word package in this document has its usual meaning: a set of related files distributed, installed, and maintained as a unit This is not a package, which is a style file supplementing a document classWe use the following typographic conventions: literal Literal text such as filename is typeset in typewriter type replaceable Replaceable text such as package, identifying a class of things, is typeset in italics inside angle brackets
2GeneralThis section describes common properties throughout the TDS tree 2.1Subdirectory searchingMany installations store large numbers of related files in single directories, for example, all TFM files andor all input filesThis monolithic arrangement hinders maintenance of a system: it is difficult to determine what files are used by what packages, what files need to be updated when a new version is installed, or what files should be deleted if a package is removed It is also a source of error if two or more packages happen to have input files with the same nameTherefore, the TWG felt each package should be in a separate directory But we recognized that explicitly listing all directories to be searched would be unbearable A site may wish to install dozens of packages Aside from anything else, listing that many directories would produce search paths many thousands of characters long, overflowing the available space on some systemsAlso, if all directories are explicitly listed, installing or removing a new package would mean changing a path as well as installing or removing the actual files This would be a timeconsuming and errorprone operation, even with implementations that provide some way to specify the directories to search at runtime On systems without runtime configuration, it would require recompiling software, an intolerable burdenAs a result, the TWG concluded that a comprehensive TDS requires implementations to support some form of implicit subdirectory searching More precisely, implementations must make it possible to specify that , MetaFont, and their companion utilities search in both a specified directory and recursively through all subdirectories of that directory when looking for an input file Other forms of subdirectory searching, for example recursivetoonelevel searches, may also be provided We encourage implementors to provide subdirectory searching at the option of the installer and user for all pathsThe TDS does not specify a syntax for specifying recursive searching, but we encourage implementors to provide interoperability (see Appendixiref="sec:More-on-subdirectory-searching"sec:More-on-subdirectory-searching) 2.2Rooting the treeIn this document, we shall designate the root TDS directory by texmf (for and MetaFont) We recommend using that name where possible, but the actual name of the directory is up to the installer On pc networks, for example, this could map to a logical drive specification such as T:Similarly, the location of this directory on the system is sitedependent It may be at the root of the file system; on Unix systems, usrlocalshare, usrlocal, usrlocallib, and opt are common choicesThe name texmf was chosen for several reasons: it reflects the fact that the directory contains files pertaining to an entire system (including MetaFont, MetaPost, BibTeX, etc.), not just itself; and it is descriptive of a generic installation rather than a particular implementationA site may choose to have more than one TDS hierarchy installed (for example, when installing an upgrade) This is perfectly legitimate 2.3Local additionsThe TDS cannot specify precisely when a package is or is not a local addition Each site must determine this according to its own conventions At the two extremes, one site might wish to consider nonlocal all files not acquired as part of the installed distribution; another site might consider local only those files that were actually developed at the local site and not distributed elsewhereWe recognize two common methods for local additions to a distributed texmf tree Both have their place; in fact, some sites may employ both simultaneously: A completely separate tree which is a TDS structure itself; for example, usrlocalumbtex at the University of Massachusetts at Boston This is another example of the multiple texmf hierarchies mentioned in the previous section A directory named local at any appropriate level, for example, in the format, package, and supplier directories discussed in the following sections The TDS reserves the directory name local for this purpose We recommend using local for siteadapted configuration files, such as language.dat for the Babel package or graphics.cfg for the graphics package Unmodified configuration files from a package should remain in the package directory The intent is to separate locally modified or created files from distribution files, to ease installing new releases One common case of local additions is dynamically generated files, e.g., PK fonts by the MakeTeXPK script originated by Dvips A site may store the generated files directly in any of: their standard location in the main TDS tree (if it can be made globally writable); an alternative location in the main TDS tree (for example, under texmffontstmp); a second complete TDS tree (as outlined above); any other convenient directory (perhaps under var, for example varspoolfonts) No one solution will be appropriate for all sites 2.4Duplicate filenamesDifferent files by the same name may exist in a TDS tree The TDS generally leaves unspecified which of two files by the same name in a search path will be found, so generally the only way to reliably find a given file is for it to have a unique name However, the TDS requires implementations to support the following exceptions: Names of input files must be unique within each firstlevel subdirectory of texmftex and texmftexgeneric, but not within all of texmftex; i.e., different formats may have files by the same name (Sectioniref="sec:Macros"sec:Macros discusses this further.) Thus, no single formatindependent path specification, such as a recursive search beginning at texmftex specifying no other directories, suffices So implementations must provide formatdependent path specifications, for example via wrapper scripts or configuration files Many font files will have the same name (e.g., cmr10.pk), as discussed in Sectioniref="sec:Valid-font-bitmaps"sec:Valid-font-bitmaps Implementations must distinguish these files by mode and resolution All implementations we know of already have these capabilitiesOne place where duplicate names are likely to occur is not an exception: Names of MetaFont input files (as opposed to bitmaps) must be unique within all of texmffonts In practice, this is a problem with some variants of Computer Modern which contain slightly modified files named punct.mf, romanl.mf, and so on We believe the only feasible solution is to rename the derivative files to be unique
3Toplevel directoriesThe directories under the texmf root identify the major components of a system (see Sectioniref="sec:Summary"sec:Summary for a summary) A site may omit any unneeded directoriesAlthough the TDS by its nature can specify precise locations only for implementationindependent files, we recognize that installers may well wish to place other files under texmf to simplify administration of the tree, especially if it is maintained by someone other than the system administrator Therefore, additional toplevel directories may be presentThe toplevel directories specified by the TDS are: texfor files (Sectioniref="sec:Macros"sec:Macros) fontsfor fontrelated files (Sectioniref="sec:Fonts"sec:Fonts) metafontfor MetaFont files which are not fonts (Sectioniref="sec:Non-font-MF-files"sec:Non-font-MF-files) metapostfor MetaPost files (Sectioniref="sec:MetaPost"sec:MetaPost) bibtexfor BibTeX files (Sectioniref="sec:BibTeX"sec:BibTeX) docfor user documentation (Sectioniref="sec:Documentation"sec:Documentation) source for sources This includes both traditional program sources (for example, Web2c sources go in texmfsourceweb2c) and, e.g., dtx sources (which go in texmfsourcelatex) The TDS leaves unspecified any structure under source source is intended for files which are not needed at runtime by any program; it should not be included in any search path For example, plain.tex does not belong under texmfsource, even though it is a source file in the sense of not being derived from another file (It goes in texmftexplainbase, as explained in Sectioniref="sec:Macros"sec:Macros) implementation for implementations (examples: emtex, web2c), to be used for whatever purpose deemed suitable by the implementor or administrator Files that cannot be shared between implementations, such as pool files (tex.pool) and memory dump files (plain.fmt) go here, in addition to implementationwide configuration files See Appendixiref="sec:Example-implementation-specific-trees"sec:Example-implementation-specific-trees for examples of real implementation trees extension for programspecific input files for new programs (examples: etex, pdftex, omega) that are extensions of , MetaFont, or any standard program See Sectioniref="sec:Extensions"sec:Extensions program for programspecific input and configuration files for any related programs (examples: mft, dvips) In fact, the tex, metafont, metapost, bibtex, and extension items above may all be seen as instances of this case 3.1Macros macro files shall be stored in separate directories, segregated by format and package name (we use format in its traditional sense to mean a usefully dumpable package): texmftexformatpackage format is a format name (examples: amstex, latex, plain, texinfo) The TDS allows distributions that can be used as either formats or packages (e.g., Texinfo, Eplain) to be stored at either level, at the option of the format author or administrator We recommend that packages used as formats at a particular site be stored at the format level: by adjusting the inputs search path, it will be straightforward to use them as macro packages under another format, whereas placing them in another tree completely obscures their use as a formatThe TDS reserves the following format names: generic, for input files that are useful across a wide range of formats (examples: null.tex, path.sty) Generally, this means any format that uses the category codes of Plain and does not rely on any particular format This is in contrast to those files which are useful only with Plain (which go under texmftexplain), e.g., testfont.tex and plain.tex itself local, for local additions See Sectioniref="sec:Local-additions"sec:Local-additions Thus, for almost every format, it is necessary to search at least the format directory and then the generic directory (in that order) Other directories may need to be searched as well, depending on the format When using AMS, for example, the amstex, plain, and generic directories should be searched, because AMS is compatible with Plain package is a package name (examples: babel, texdraw) In the case where a format consists of only a single file and has no auxiliary packages, that file can simply be placed in the format directory, instead of formatbase For example, Texinfo goes in texmftextexinfotexinfo.tex, not texmftextexinfobasetexinfo.texThe TDS reserves the following package names: base, for the base distribution of each format, including files used by initex when dumping format files For example, in the standard distribution, the ltx files created during the build process shall be stored in the base directory hyphen, for hyphenation patterns, including the original American English hyphen.tex These are typically used only by initex In most situations, this directory need exist only under the generic format images, for image input files, such as Encapsulated PostScript figures Although it is somewhat nonintuitive for these to be under a directory named tex, needs to read these files to glean bounding box or other information A mechanism for sharing image inputs between and other typesetting programs (e.g., Interleaf, FrameMaker) is beyond the scope of the TDS In most situations, this directory need exist only under the generic format local, for local additions and configuration files See Sectioniref="sec:Local-additions"sec:Local-additions misc, for packages that consist of a single file An administrator or package maintainer may create directories for singlefile packages at his discretion, instead of using misc 3.2FontsFont files shall be stored in separate directories, segregated by file type, font supplier, and typeface (PK and GF files need additional structure, as detailed in the next section):texmffontstypesuppliertypeface type is the type of font file The TDS reserves the following type names: afm, for Adobe font metricsgf, for generic font bitmap filespk, for packed bitmap filessource, for font sources (MetaFont files, property lists, etc.)tfm, for font metric filestype1, for Type 1 fonts (in any format)vf, for virtual fonts As usual, a site may omit any of these directories that are unnecessary (gf is a particularly likely candidate for omission) supplier is a name identifying font source (examples: adobe, ams, public) The TDS reserves the following supplier names: ams, for the American Mathematical Societys AMSfonts collection local, for local additions See Sectioniref="sec:Local-additions"sec:Local-additions public, for freely redistributable fonts where the supplier neither (1)requested its own directory (e.g., ams), nor (2)also made proprietary fonts (e.g., adobe) It does not contain all extant freely distributable fonts, nor are all files therein necessarily strictly public domain tmp, for dynamicallygenerated fonts, as is traditional on some systems It may be omitted if unnecessary, as usual typeface is the name of a typeface family (examples: cm, euler, times) The TDS reserves the following typeface names: cm (within public), for the 75 fonts defined in Computers and Typesetting, VolumeE latex (within public), for those fonts distributed with in the base distribution local, for local additions See Sectioniref="sec:Local-additions"sec:Local-additions Some concrete examples: texmffontssourcepublicpandorapnr10.mftexmffontstfmpubliccmcmr10.tfmtexmffontstype1adobeutopiaputr.pfaFor complete supplier and typeface name lists, consult Filenames for fonts (see Appendixiref="sec:Related-references"sec:Related-references) 3.2.1Font bitmapsFont bitmap files require two characteristics in addition to the above to be uniquely identifiable: (1)the type of device (i.e., mode) for which the font was created; (2)the resolution of the bitmapFollowing common practice, the TDS segregates fonts with different device types into separate directories See modes.mf in Appendixiref="sec:Related-references"sec:Related-references for recommended mode namesSome printers operate at more than one resolution (e.g., at 300dpi and 600dpi), but each such resolution will necessarily have a different mode name Nothing further is needed, since implicit in the system is the assumption of a single target resolutionTwo naming strategies are commonly used to identify the resolution of bitmap font files On systems that allow long filenames (and in the original MetaFont program itself), the resolution is included in the filename (e.g., cmr10.300pk) On systems which do not support long filenames, fonts are generally segregated into directories by resolution (e.g., dpi300cmr10.pk)Because the TDS cannot require long filenames, we must use the latter scheme for naming fonts So we have two more subdirectory levels under pk and gf: texmffontspkmodesuppliertypefacedpinnntexmffontsgfmodesuppliertypefacedpinnn mode is a name which identifies the device type (examples: cx, ljfour, modeless) Usually, this is the name of the MetaFont mode used to build the PK file For fonts rendered as bitmaps by a program that does not distinguish between different output devices, the mode name shall be simply modeless The mode level shall not be omitted, even if only a single mode happens to be in use dpinnn specifies the resolution of the font (examples: dpi300, dpi329) dpi stands for dots per inch, i.e., pixels per inch We recognize that pixels per millimeter is used in many parts of the world, but dpi is too traditional in the world to consider changing now The integer nnn is to be calculated as if using MetaFont arithmetic and then rounded; i.e., it is the integer MetaFont uses in its output gf filename We recognize small differences in the resolution are a common cause of frustration among users, however, and recommend implementors follow the level0 DVI driver standard (see Appendixiref="sec:Related-references"sec:Related-references) in bitmap font searches by allowing a fuzz of 0.2 (with a minimum of 1) in the dpi Implementations may provide extensions to the basic naming scheme, such as long filenames (as in the original MetaFont) and font library files (as in ems .fli files), provided that the basic scheme is also supported 3.2.2Valid font bitmapsThe TWG recognizes that the use of short filenames has many disadvantages The most vexing is that it results in the creation of dozens of different files with the same name At a typical site, cmr10.pk will be the filename for Computer Modern Roman 10pt at 510 magnifications for 23 modes (Sectioniref="sec:Duplicate-filenames"sec:Duplicate-filenames discusses duplicate filenames in general.)To minimize this problem, we strongly recommend that PK files contain enough information to identify precisely how they were created: at least the mode, base resolution, and magnification used to create the fontThis information is easy to supply: a simple addition to the local modes used for building the fonts with MetaFont will automatically provide the required information If you have been using a local modes file derived from (or that is simply) modes.mf (see Appendixiref="sec:Related-references"sec:Related-references), the required information is already in your PK files If not, a simple addition based on the code found in modes.mf can be made to your local modes file and the PK files rebuilt 3.3Nonfont MetaFont filesMost MetaFont input files are font programs or parts of font programs and are thus covered by the previous section However, a few nonfont input files do exist Such files shall be stored in:texmfmetafontpackagepackage is the name of a MetaFont package (for example, mfpic)The TDS reserves the following package names: base, for the standard MetaFont macro files as described in The MetaFontbook, such as plain.mf and expr.mf local, for local additions See Sectioniref="sec:Local-additions"sec:Local-additions misc, for MetaFont packages consisting of only a single file (for example, modes.mf) An administrator or package maintainer may create directories for singlefile packages at his discretion, instead of using misc 3.4MetaPostMetaPost is a picturedrawing language developed by John Hobby, derived from Knuths MetaFont Its primary purpose is to output Encapsulated PostScript instead of bitmapsMetaPost input files and the support files for MetaPostrelated utilities shall be stored in:texmfmetapostpackagepackage is the name of a MetaPost package At the present writing none exist, but the TWG thought it prudent to leave room for contributed packages that might be written in the futureThe TDS reserves the following package names: base, for the standard MetaPost macro files, such as plain.mp, mfplain.mp, boxes.mp, and graph.mp This includes files used by inimp when dumping mem files containing preloaded macro definitions local, for local additions See Sectioniref="sec:Local-additions"sec:Local-additions misc, for MetaPost packages consisting of only a single file An administrator or package maintainer may create directories for singlefile packages at his discretion, instead of using misc support, for additional input files required by MetaPost utility programs, including a font map, a character adjustment table, and a subdirectory containing lowlevel MetaPost programs for rendering some special characters 3.5BibTeXBibTeXrelated files shall be stored in: texmfbibtexbibpackagetexmfbibtexbstpackageThe bib directory is for BibTeX database (.bib) files, the bst directory for style (.bst) filespackage is the name of a BibTeX package The TDS reserves the following package names (the same names are reserved under both bib and bst): base, for the standard BibTeX databases and styles, such as xampl.bib, plain.bst local, for local additions See Sectioniref="sec:Local-additions"sec:Local-additions misc, for BibTeX packages consisting of only a single file An administrator or package maintainer may create directories for singlefile packages at his discretion, instead of using misc 3.6DocumentationMost packages come with some form of documentation: user manuals, example files, programming guides, etc In addition, many independent files not part of a macro or other package describe various aspects of the systemThe TDS specifies that these additional documentation files shall be stored in a structure that parallels to some extent the fonts and tex directories, as follows:texmfdoccategory...category identifies the general topic of documentation that resides below it; for example, a format name (latex), program name (bibtex, tex), language (french, german), or other system components (web, fonts)The TDS reserves the following categories: Within each category tree for a format, the directory base is reserved for base documentation distributed by the formats maintainers general, for standalone documents not specific to any particular program (for example, Joachim Schrods Components of ) help, for metainformation, such as faqs, David Jones macro index, etc html, for html documents info, for processed Texinfo documents (Info files, like anything else, may also be stored outside the TDS, at the installers option.) local, for local additions See Sectioniref="sec:Local-additions"sec:Local-additions The doc directory is intended for implementationindependent and operating systemindependent documentation files Implementationdependent files shall be stored elsewhere, as provided for by the implementation andor administrator (for example, VMS help files under texmfvmshelp)The documentation directories may contain sources, DVI files, PostScript files, text files, example input files, or any other useful documentation format(s)See Sectioniref="sec:Documentation-tree-summary"sec:Documentation-tree-summary for a summary 3.7ExtensionsNew programs that are extensions of old ones shall use a new toplevel directory name for their extensionspecific input files The new directory shall have the same general structure as the toplevel directory of the original program, and the new program almost certainly should search the original toplevel directoryFor example, several variants of that recognize additional commands have been released Input files that use these new commands cannot be placed in the toplevel tex directory, since the original program cannot read them So they must go in a new directory, with the same package structure as tex (see Sectioniref="sec:Macros"sec:Macros)Using e as an example, we have the following: A new toplevel (in texmf) directory etex Since e is an extension of , texmfetex follows the same conventions as texmftex texmfetex contains only especific files e searches first texmfetex, then texmftex These same principles hold for PDF, Omega, and (most probably) future variants of or MetaFont pagebreak
4SummaryA skeleton of a TDS texmf directory tree This is not to imply these are the only entries allowed For example, local may occur at any level ll bibtex BibTeX input files . bib BibTeX databases . . base base distribution (e.g., xampl.bib) . . misc singlefile databases . package name of a package . bst BibTeX style files . . base base distribution (e.g., plain.bst, acm.bst) . . misc singlefile styles . package name of a package doc see Sectioniref="sec:Documentation"sec:Documentation and the summary below etex as with tex, below fonts fontrelated files . type file type (e.g., pk) . . mode type of output device (for pk and gf only) . . . supplier name of a font supplier (e.g., public) . . . . typeface name of a typeface (e.g., cm) . . . . . dpinnn font resolution (for pk and gf only) implementation implementations, by name (e.g., emtex) local files created or modified at the local site metafont MetaFont (nonfont) input files . base base distribution (e.g., plain.mf) . misc singlefile packages (e.g., modes.mf) . package name of a package (e.g., mfpic) metapost MetaPost input and support files . base base distribution (e.g., plain.mp) . misc singlefile packages . package name of a package . support support files for MetaPostrelated utilities mft MFT inputs (e.g., plain.mft) program related programs, by name (e.g., dvips) source program source code by name (e.g., latex, web2c) tex input files . format name of a format (e.g., plain) . . base base distribution for format (e.g., plain.tex) . . misc singlefile packages (e.g., webmac.tex) . . local local additions to or local configuration files for format . . package name of a package (e.g., graphics, mfnfss) . generic formatindependent packages . . hyphen hyphenation patterns (e.g., hyphen.tex) . . images image input files (e.g., Encapsulated PostScript) . . misc singlefile formatindependent packages (e.g., null.tex) . . package name of a package (e.g., babel) pagebreak 4.1Documentation tree summaryA skeleton of a TDS directory tree under texmfdoc This is not to imply these are the only entries allowed ll ams . amsfonts amsfonts.faq, amfndoc . amslatex amslatex.faq, amsldoc . amstex amsguide, joyerr bibtex BibTeX . base btxdoc.tex fonts . fontname Filenames for fonts . oldgerm corkpapr format name of a format (e.g., generic, latex) . base for the base distribution . misc for contributed singlefile package documentation . package for package general across programs, generalities . errata errata, errata[18] . texcomp Components of generic for nonformatspecific packages . babel . german germdoc help metainformation . ctan info about CTAN mirror sites . faq faqs of comp.text.tex, etc html html files info gnu Info files, made from Texinfo sources latex example of format . base ltnews, guide, etc . graphics grfguide local sitespecific documentation program related programs, by name (examples follow) metafont mfbook.tex, metafontforbeginners, etc metapost mpman, manfig, etc tex texbook.tex, A Gentle Introduction to , etc web webman, cwebman
pagebreakAppendices
AppendixAUnspecified piecesThe TDS cannot address the following aspects of a functioning system: The location of executable programs: this is too sitedependent even to recommend a location, let alone require one A site may place executables outside the texmf tree altogether (e.g., usrlocalbin), in a platformdependent directory within texmf, or elsewhere Upgrading packages when new releases are made: we could find no way of introducing version specifiers into texmf that would do more good than harm, or that would be practical for even a plurality of installations The location of implementationspecific files (e.g., .fmt files): by their nature, these must be left to the implementor or maintainer See Appendixiref="sec:Example-implementation-specific-trees"sec:Example-implementation-specific-trees Precisely when a package or file should be considered local, and where such local files are installed See Sectioniref="sec:Local-additions"sec:Local-additions for more discussion A.1Portable filenamesThe TDS cannot require any particular restriction on filenames in the tree, since the names of many existing files conform to no standard scheme For the benefit of people who wish to make a portable distribution or installation, however, we outline here the necessary restrictions The TDS specifications themselves are compatible with theseISO9660 is the only universally acceptable file system format for CDROMs A subset thereof meets the stringent limitations of all operating systems in use today It specifies the following: File and directory names, not including any directory path or extension part, may not exceed eight characters Filenames may have a single extension Extensions may not exceed three characters Directory names may not have an extension Names and extensions may consist of only the characters AZ, 09, and underscore Lowercase letters are excluded A period separates the filename from the extension and is always present, even if the name or extension is missing (e.g., FILENAME. or .EXT) A version number, ranging from 132767, is appended to the file extension, separated by a semicolon (e.g., FILENAME.EXT;1) Only eight directory levels are allowed, including the toplevel (mounted) directory (see Sectioniref="sec:Rooting-the-tree"sec:Rooting-the-tree) Thus, the deepest valid ISO9660 path is: texmfL2L3L4L5L6L7L8FOOBAR;112345678 The deepest TDS path needs only seven levels: texmffontspkcxpubliccmdpi300cmr10pk1234567 Some systems display a modified format of ISO9660 names, mapping alphabetic characters to lowercase, removing version numbers and trailing periods, etcBefore the December 1996 release, used mixedcase names for font descriptor files Fortunately, it never relied on case alone to distinguish among the files Nowadays, it uses only monocase names
AppendixBImplementation issuesWe believe that the TDS can bring a great deal of order to the current anarchic state of many installations In addition, by providing a common frame of reference, it will ease the burden of documenting administrative tasks Finally, it is a necessary part of any reasonable system of true dropin distribution packages for B.1Adoption of the TDS[This section is retained purely for historical purposes; the TDS is now quite firmly entrenched in most distributions.]We recognize that adoption of TDS will not be immediate or universal Most administrators will not be inclined to make the final switch until: Clear and demonstrable benefits can be shown for the TDSTDScompliant versions of all key programs are available in ported, welltested formsA settling period has taken place, to flush out problems The public release of the first draft of this document was the first step in this processConsequently, most of the first trials of the TDS will be made by members of the TDS committee andor developers of related software This has already taken place during the course of our deliberations (see Appendixiref="sec:Related-references"sec:Related-references for a sample tree available electronically) They will certainly result in the production of a substantial number of TDScompliant packages Indeed, the te and Live distributions are TDScompliant and in use now at many sitesOnce installable forms of key TDScompliant packages are more widespread, some administrators will set up TDScompliant trees, possibly in parallel to existing production directories This testing will likely flush out problems that were not obvious in the confined settings of the developers sites; for example, it should help to resolve OS and package dependencies, package interdependencies, and other details not addressed by this TDS versionAfter most of the dust has settled, hopefully even conservative administrators will begin to adopt the TDS Eventually, most sites will have adopted the common structure, and most packages will be readily available in TDScompliant formWe believe that this process will occur relatively quickly The TDS committee spans a wide range of interests in the community Consequently, we believe that most of the key issues involved in defining a workable TDS definition have been covered, often in detail developers have been consulted about implementation issues, and have been trying out the TDS arrangement Thus, we hope for few surprises as implementations matureFinally, there are several (current or prospective) publishers of CDROMs These publishers are highly motivated to work out details of TDS implementation, and their products will provide inexpensive and convenient ways for experimentallyminded administrators to experiment with the TDSEfforts are under way to set up a TDS Registry that will coordinate assignment of TDScompliant directory names and provide a definitive database of TDScompliant software distributions (Perhaps this could also serve many sites as the definition of when a package is local.) For now, distribution through CTAN serves as an imprecise registry B.2More on subdirectory searchingRecursive subdirectory searching is the ability to specify a search not only of a specified directory d, but recursively of all directories below dSince the TDS specifies precise locations for most files, with no extra levels of subdirectories allowed, true recursive searching is not actually required for a TDScompliant implementation We do, however, strongly recommend recursive searching as the most userfriendly and natural approach to the problem, rather than convoluted methods to specify paths without recursionThis feature is already supported by many implementations of and companion utilities, for example DECUS for VMS, Dvips(k), em (and its drivers), PubliC , Web2c, Xdvi(k), and YY The Kpathsea library is a reusable implementation of subdirectory searching for , used in a number of the above programsEven if your implementation does not directly support subdirectory searching, you may find it useful to adopt the structure if you do not use many fonts or packages For instance, if you only use Computer Modern and ams fonts, it would be feasible to store them in the TDS layout and list the directories individually in configuration files or environment variablesThe TWG recognizes that subdirectory searching places an extra burden on the system and may be the source of performance bottlenecks, particularly on slower machines Nevertheless, we feel that subdirectory searching is imperative for a wellorganized TDS, for the reasons stated in Sectioniref="sec:Subdirectory-searching"sec:Subdirectory-searching Implementors are encouraged to provide enhancements to the basic principle of subdirectory searching to avoid performance problems, e.g., the use of a filename cache (this can be as simple as a recursive directory listing) that is consulted before disk searching begins If a match is found in the database, subdirectory searching is not required, and performance is thus independent of the number of subdirectories present on the systemDifferent implementations specify subdirectory searching differently In the interest of typographic clarity, the examples here do not use the replaceable font Dvips: via a separate TEXFONTSSUBDIR environment variable em: t:subdir; t:subdir for a single level of searching Kpathsea: texmfsubdir VMS: texmf:[subdir...] Xdvi (patchlevel 20): texmfsubdir; texmfsubdir for a single level of searching Version 20.50 and above support the notation YY : t:subdir or t:subdir B.3Example implementationspecific treesThe TDS cannot specify a precise location for implementationspecific files, such as texmfini, because a site may have multiple implementationsNevertheless, for informative purposes, we provide here the default locations for some implementations Please contact us with additions or corrections These paths are not definitive, may not match anything at your site, and may change without warningWe recommend all implementations have default search paths that start with the current directory (e.g., .) Allowing users to include the parent directory (e.g., ..) is also helpful B.3.1AmiWeb2c 2.0(Email schererphysik.rwthaachen.de to contact the maintainer of this implementation.)AmiWeb2c 2 is compatible with Web2c 7 to the greatest possible extent, so only the very few differences are described in this section Detailed information about the basic concepts is given in the section for Web2c 7 belowThanks to the SELFAUTO mechanism of Kpathsea 3.0 no specific location for the installation of AmiWeb2c is required as long as the general structure of the distribution is preservedIn addition to Kpathseas notation recursive path search may also be started by DEVICE:, e.g., TeXMF: will scan this specific device completelyBinaries coming with the AmiWeb2c distribution are installed in the directory binamiweb2c outside the common TDS tree sharetexmf In addition to the set of AmiWeb2c binaries you will find two subdirectories local and pastex with auxiliary programsA stripped version of the Pas system (used by kind permission of Georg Hemann) is coming with AmiWeb2c, preinstalled in its own sharetexmfamiweb2cpastex directory If you want to use Pas you have to assign the name TeX: to this placeDocumentation files in AmigaGuide format should be stored at docguide similar to docinfo B.3.2Public DECUS If another VMS implementation besides Public DECUS appears, the top level implementation directory name will be modified to something more specific (e.g., vmsdecus) ll texmf . vms VMS implementation specific files . . exe enduser commands . . . common command procedures, command definition files, etc . . . axp binary executables for Alpha AXP . . . vax binary executables for VAX . . formats pool files, formats, bases . . help VMS help library, and miscellaneous help sources . . mgr command procedures, programs, docs, etc., for system management B.3.3Web2c 7All implementationdependent system files (.pool, .fmt, .base, .mem) are stored by default directly in texmfweb2c The configuration file texmf.cnf and various subsidiary MakeTeX... scripts used as subroutines are also stored thereNon specific files are stored following the GNU coding standards Given a root directory prefix (usrlocal by default), we have default locations as follows: ll prefix installation root (usrlocal by default) . bin executables . man man pages . info info files . lib libraries (libkpathsea.) . share architectureindependent files . . texmf TDS root . . . web2c implementationdependent files (.pool, .fmt, texmf.cnf, etc.)See ftp://ftp.gnu.org/pub/gnu/standards.text for the rationale behind and descriptions of this arrangement A site may of course override these defaults; for example, it may put everything under a single directory such as usrlocaltexmf
AppendixCIs there a better way?Defining the TDS required many compromises Both the overall structure and the details of the individual directories were arrived at by finding common ground among many opinions The driving forces were feasibility (in terms of what could technically be done and what could reasonably be expected from developers) and regularity (files grouped together in an arrangement that made sense)Some interesting ideas could not be applied due to implementations lacking the necessary support: Path searching control at the level If documents could restrict subdirectory searching to a subdirectory via some portable syntax in file names, restrictions on uniqueness of filenames could be relaxed considerably (with the cooperation of the formats), and the search path would not need to depend on the format Multiple logical texmf trees For example, a site might have one (readonly) location for stable files, and a different (writable) location for dynamicallycreated fonts or other files It would be reasonable for two such trees to be logically merged when searching C.1Macro structureThe TWG settled on the formatpackage arrangement after long discussion about how best to arrange the filesThe primary alternative to this arrangement was a scheme which reversed the order of these directories: packageformat This reversed arrangement has a strong appeal: it keeps all of the files related to a particular package in a single place The arrangement actually adopted tends to spread files out into two or three places (macros, documentation, and fonts, for example, are spread into different sections of the tree right at the top level)Nevertheless, the formatpackage structure won for a couple of reasons: It is closer to current practice; in fact, several members of the TWG have already implemented the TDS hierarchy The alternative is not in use at any known site, and the TWG felt it wrong to mandate something with which there is no practical experience The alternative arrangement increases the number of toplevel directories, so the files that must be found using subdirectory searching are spread out in a wide, shallow tree This could have a profound impact on the efficiency of subdirectory searching C.2Font structureThe TWG struggled more with the font directory structure than anything else This is not surprising; the need to use the proliferation of PostScript fonts with is what made the previous arrangement with all files in a single directory untenable, and therefore what initiated the TDS effort C.2.1Font file type locationWe considered the supplierfirst arrangement in use at many sites:texmffontssuppliertypefacetypeThis improves the maintainability of the font tree, since all files comprising a given typeface are in one place, but unless all the programs that search this tree employ some form of caching, there are serious performance concerns For example, in order to find a TFM file, the simplest implementation would require to search through all the directories that contain PK files in all modes and at all resolutionsIn the end, a poll of developers revealed considerable resistance to implementing sufficient caching mechanisms, so this arrangement was abandoned The TDS arrangement allows the search tree to be restricted to the correct type of file, at least Concerns about efficiency remain, but there seems to be no more we can do without abandoning subdirectory searching entirelyWe also considered segregating all fontrelated files strictly by file type, so that MetaFont sources would be in a directory texmffontsmf, property list files in texmffontspl, the various forms of Type1 fonts separated, and so on Although more blindly consistent, we felt that the drawback of more complicated path constructions outweighed this The TDS merges file types (mf and pl under source, pfa and pfb and gsf under type1) where beneficial C.2.2Mode and resolution locationWe considered having the mode at the bottom of the font tree: texmffontspksuppliertypefacemodedpiIn this case, however, it is difficult to limit subdirectory searching to the mode required for a particular deviceWe then considered moving the dpinnn up to below the mode: texmffontspkmodedpisuppliertypefaceBut then it is not feasible to omit the dpinnn level altogether on systems which can and do choose to use long filenames C.2.3Modeless bitmapsThe TDS specifies using a single directory modeless as the mode name for those utilities which generate bitmaps, e.g., texmffontsmodelesstimes This has the considerable advantage of not requiring each such directory name to be listed in a search pathAn alternative was to use the utility name below which all such directories could be gathered That has the advantage of separating, say, gsftopkgenerated bitmaps from ps2pkgenerated ones However, we decided this was not necessary; most sites will use only one program for the purpose Also, PK and GF fonts generally identify their creator in the font comment following the PKID byteWe are making an implicit assumption that MetaFont is the only program producing modedependent bitmaps If this becomes false we could add an abbreviation for the program to mode names, as in mfcx vs.\ xyzcx for a hypothetical program Xyz, or we could at that time add an additional program name level uniformly to the tree It seemed more important to concisely represent the current situation than to worry about hypothetical possibilities that may never happen C.3Documentation structureWe considered placing additional documentation files in the same directory as the source files for the packages, but we felt that users should be able to find documentation separately from sources, since most users have no interest in sourcesWe hope that a separate, but parallel, structure for documentation would (1)keep the documentation together and (2)make it as straightforward as possible for users to find the particular documentation they were after
AppendixDRelated referencesThis appendix gives pointers to related files and other documentsIn this document, CTAN: means the root of an anonymous ftp CTAN tree This is both a host name and a directory name For example: ftp://ctan.tug.org/tex-archiveftp://ftp.dante.de/tex-archiveftp://ftp.tex.ac.uk/tex-archiveFinger ctantug.org for a complete list of CTAN sites, there are mirrors worldwideHere are the references: The TDS mailing list archives can be retrieved via ftp from: ftp://ftp.tug.org/mail/archives/twg-tds/ ftp://vms.rhbnc.ac.uk/archives/twg.tds. A sample TDS tree: CTAN:tds A collection of BibTeX databases and styles: ftp://ftp.math.utah.edu/pub/tex/bib Components of by Joachim Schrod: CTAN:documentationcomponentsofTeX The level0 DVI driver standard: CTAN:dviwaredrivstandardlevel0 Filenames for fonts: CTAN:documentationfontname This distribution includes recommended supplier and typeface names ISO9660 CDROM file system standard: http://www.iso.ch/cate/cat.html A complete set of MetaFont modes: CTAN:fontsmodesmodes.mf This file includes recommended mode names
AppendixEContributorsThe TWG had no formal meetings; electronic mail was the primary communication mediumSebastian Rahtz is the Users Group Technical Council liaison Norman Walsh is the committee chairOriginal contributors: BarbaraBeetonKarlBerryVickiBrownDavidCarlisleThomasEsserAlanJeffreyJorgKnappenPierreMacKayRichMorinSebastianRahtzJoachimSchrodChristianSpielerElizabethTachikawaPhilipTaylorUlrikViethPaulVojtaNormanWalshAdditional contributors: DavidAspinallNelsonBeebeHarrietBortonBartChildsDamianCugleyAlanDunwellMichaelFergusonErikFrambachBernardGaulleJeffreyGealowGeorgeGreenwadeThomasHerterBertholdHornCharlesKarneyDavidKastrupDavidKellermanWonkooKimRichardKinchRobinKirkhamAlexKokEberhardMattesBobMorrisLennyMuellnerOrenPatashnikDavidRheadAndreasSchererMarkSinkeAndrewTrevorrowDougWaudCheeWaiYeung