If you index the cursor BEFORE re-opening it as
a writable cursor, then the index plus the cursor
will be deleted automatically! That is,

create cursor C_XXX ...
index on cfield1 tag cfield1
m.dbf = dbf()
use (m.dbf) again in 0 shared alias C_YYY
use in C_XXX
select C_YYY
index on cfield2 tag cfield2
index on cfield3 tag cfield3
....

The SEQUENCE of actions is critical. Build at least
one index before you re-open will guarantee FoxPro
to delete them automatically.

I think Visual FoxPro should behave like Foxpro
2.6.