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IOL( ) Function
Get IOList Specification
Formats
1. In Composite String: IOL(composite$[,ERR=stmtref])
2. In Open File: IOL(chan[,ERR=stmtref])
Where:
composite$ Composite string variable whose IOLIST is to be retrieved. String
expression.
chan
Channel or logical file number whose default IOLIST is to be returned.
stmtref
Program line number or label to transfer control to.
Returns
Object value of an IOList or composite string variable.
Description
The IOL( ) function returns the object code value of an IOList for either an open file or a
composite string variable. If the specified file or string variable does not have an associated
IOLIST, ProvideX returns Error #81: Invalid IOLIST specification.
Syntax
Returns
IOL(chan:*)
Returns the IOList for the file's embedded data dictionary
IOL(chan:^)
Returns the alternate IOList
IOL(chan:KEY)
Returns the IOList for the file's external key, if any.
Note: To convert the object code into a format you can display, pass it to the LST( )
function.
Examples
0100 DIM CUST$:IOL=0110
0110 IOLIST NAME$,ADR1$,ADR2$,SMAN$
0120 PRINT LST(IOL(CUST$))
-:run
IOLIST NAME$,ADR1$,ADR2$,SMAN$
0100 OPEN (1,IOL=*)"CUSTDB" ! Open with internal IOL
0110 READ DATA FROM "" TO IOL=IOL(1) ! Clears the IOList