FocFetch contains the return code of the most recently issued NEXT or MATCH command. If the NEXT or MATCH command returned data, FocFetch is set to zero; otherwise, it is set to a non-zero value.

It is recommended that you test FocFetch in place of issuing the ON NEXT, ON NONEXT, ON MATCH, and ON NOMATCH commands: FocFetch accomplishes the same thing more efficiently.

For example:

FOR ALL NEXT CustID INTO CustOrderStack;
IF FocFetch NE 0 THEN ReadFailed();

FocFetch is a global variable; you do not need to pass it between procedures.