Click above to get retro games delivered to your door ever month!

  What is an .NSX?:

  A .NSX file, like a .CDX, is a Compound Index - an index file which can
  contain multiple indexes (called tags).  Most of the same characteristics
  of .CDX indexes apply to compound .NSXs.  However, a .CDX index file can
  have up to 99 index tags (although the practical limit is 50), while the
  tag limit in a compound .NSX index is 50.

  The SIXCDX flavor of the SIx Driver also supports Individual (.IDX)
  Indexes, whereas SIXNSX uses only one index format (.NSX) for both Compound
  and Individual Indexes.

  For example:

    INDEX ON last TO test // Creates TEST.IDX under SIXCDX
    INDEX ON last TO test // Creates TEST.NSX under SIXNSX

  The TEST.NSX file would also contain one TAG, also called TEST.  In this
  manner, it will behave just like an .NTX or .IDX file.  If, however, you
  later want to add additional TAGs into TEST.NSX, you can.

  For example, using the TEST.NSX created above, the following would add a
  second TAG called FOO into it:

    INDEX ON age TAG foo OF test
             ---     ---    ----
              .       .      .  
              |       |      +-( Index FILE name: TEST.NSX )
              |       |
              |       +-( Index TAG name: FOO )
              |
              +-( Index Expression: AGE )