module_name,...
Compile a help index file for a given module or modules.
EXAMPLES
--------

To update the index for a single module:

  0>makeindex general
  Indexing module: general
  0>

To update all module index files, omit any arguments:

  0>makeindex
  Indexing module: difmap
  Indexing module: file_io
  Indexing module: general
  Indexing module: graphics
  Indexing module: maths
  0>

ARGUMENTS
---------

module,...  -   The name(s) of one or more modules to be indexed.
                If omitted, all modules will be re-indexed.

CONTEXT
-------
In order that the 'apropos' and 'help module' commands be reasonably fast,
it is essential that they don't have to open every help file in order to
extract the one-line description that is on the second line of every
help file. Instead, these commands look for files named after each
module in the program, with an '.idx' extension. These index files
contain the list of help topics, commands and functions, together with
their one-line descriptions. They are created by the 'makeindex'
command, which should be called whenever a help file is added,
removed, or modified such that its one-line description is changed.