fontname: Name mapping file

 
 3.1 A fontname mapping file
 ===========================
 
 At the moment, most implementations of TeX look up a TFM file (as part
 of the `\font' command), by searching for a file with the name given by
 the user (possibly in any of series of directories).  But if we also
 looked TFM names up in _another_ file (or set of files), which
 specifies the actual filename, the fontname given in the TeX source
 file could be almost anything at all, of any length.
 
    In version 5.851d of Web2c, I implemented this mapping file.  Each
 file `texfonts.map' in a search path is read for abbreviations. The file
 has a straightforward format: each line specifies the filename and the
 TeX name for one font, separated by whitespace.  Extra information on
 the line is ignored; then more information could be specified for the
 benefit of DVI-reading programs in the same file.  Comments start with
 `%' and continue to the end of the line.
 
    Besides allowing long names, this sort of mapping file has other
 benefits.  TeX source or DVI files can be more easily transported,
 because the font names in a particular file can be made to work on every
 system.  Also, when combined with a consistent naming scheme, macros
 could be written to access any of a number of fonts.  Right now, each
 font family has to have specialized macros written to deal with it.
 
    Incidentally, Professor Knuth has approved this as a legitimate
 "system-dependent" extension; a TeX with such a feature can still be
 called "TeX".