Purpose
Returns the system null pointer value. 
Syntax
SYSNULL()
 or 
SYSNULL
The second syntax form can be used only when the BUILTIN attribute is specified. 
Examples
IF LAST_POINTER = SYSNULL() THEN CALL FINISH;
In this example, the IF statement determines whether the pointer variable LAST_POINTER is system null; if so, the CALL statement executes. 
 
Description
The SYSNULL function returns a null pointer value. The SYSNULL value is 0.
This value cannot be changed by the -setnull compiler option, which applies only to the NULL built-in. For a description of the -setnull compiler option, see your Open PL/I User's Guide.