+---------------------------------+
|             SYS(21)             |
+---------------------------------+

-----------------------------------
Returns number of master controlling index or index tag in selected work
area.
Return value - Character
-----------------------------------

The master controlling index or index tag is the first index or index
tag specified in a USE or SET INDEX command.  The SET ORDER command may
also be used to specify which index or index tag is to be the master
controlling index or index tag.

For more information about the master controlling index and index tag,
see the USE and SET ORDER commands in this help facility.

+---------------------------------+
|             Example             |
+---------------------------------+
USE customer INDEX cus_cus.idx, cus_com.idx
? SYS(21)
SET ORDER TO 2
? SYS(21)

-----------------------------------

See Also:  CDX(), KEY(), INDEX, MDX(), NDX(), REINDEX, SET INDEX, SET
ORDER, SYS(), SYS(22) Master tag/index name, TAG(), USE

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