This routine returns the number of bytes actually passed by the caller for a particular parameter.
Usage
CALL "C$PARAMSIZE"
USING PARAM-NUM,
GIVING PARAM-SIZE
Parameters
PARAM-NUM Numeric parameter
This value is the ordinal position in the Procedure Division's USING phrase of the parameter whose size you want to know.
PARAM-SIZE Any numeric data item
This item receives the number of bytes in the data item actually passed by the caller.
Description
This routine returns the actual size (in bytes) of a data item passed to the current program by its caller. You pass the number (starting with "1") of the data item in the Procedure Division's USING phrase, and C$PARAMSIZE will return the size of the corresponding item that was actually passed. This can be useful for handling data items of unknown size.
For example, suppose that you wanted to write a routine that could convert any data item to upper-case, up to 10000 bytes in size. This routine could look like this:
IDENTIFICATION DIVISION.
PROGRAM-ID. MAKE-UPPERCASE.
DATA DIVISION.
WORKING-STORAGE SECTION.
77 PARAM-SIZE PIC 9(5).
LINKAGE SECTION.
77 PASSED-ITEM PIC X(10000).
PROCEDURE DIVISION USING PASSED-ITEM.
MAIN-LOGIC.
CALL "C$PARAMSIZE" USING 1, GIVING PARAM-SIZE
INSPECT PASSED-ITEM( 1 : PARAM-SIZE )
CONVERTING "abcdefghijklmnopqrstuvwxyz"
TO "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
EXIT PROGRAM.
In this example, if you do not use C$PARAMSIZE, you have to pass a full 10000 bytes to this routine or you get a memory usage error. By using C$PARAMSIZE and reference modification, only the memory actually passed is referenced, and there is no error. C$PARAMSIZE works only when the program is a called subroutine. It does not work with the "CALL RUN" form of the CALL verb.