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K Recursive subdirectory searching is the ability to specify that TeX (or any H program in the TeX system) should search not only a specified directory,= but recursively through all directories below that directory.
A This feature is already supported by many implementations of TeX, 4 including, but not limited to, emTeX (and its* drivers), PubliC TeX, Web2C,# Y&YTeX, dvips(k), & xdvi(k), and DECUS TeX for VMS.
F Even if your TeX 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 use8 Computer Modern and AMS fonts, you can store them in theA TDS layout and list the directories individually in configuration files or environment variables.
E The 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 thatA subdirectory searching is imperative to a well-organized TDS, for A the reasons stated above. Implementors are encouraged to provide D extensions to the basic principle of subdirectory searching to avoid= performance problems. One possible extension is the use of a 5 ``database'' of filenames (this can be as simple as a ? recursive directory listing) that is consulted before directory D searching begins. If a match is found in the database, subdirectoryE searching is not required, and performance is thus independent of the / number of subdirectories present on the system.