New programs that are extensions of old ones shall use a new top-level directory name for their extension-specific input files. The new directory shall have the same general structure as the top-level directory of the original program, and the new program almost certainly should search the original top-level directory.
For example, several variants of TeX that recognize additional commands have been released. Input files that use these new commands cannot be placed in the top-level `tex' directory, since the original TeX program cannot read them. So they must go in a new directory, with the same package structure as `tex' (see Section section Macros).
Using e-TeX as an example, we have the following:
These same principles hold for PDFTeX, Omega, and (most probably) future variants of TeX or METAFONT.
Go to the first, previous, next, last section, table of contents.