There are two different sets of default values:
global default values, which are set by the syntax file
specific SDF-P default values (see the description of the SET-PROCEDURE-OPTIONS command, "SET-PROCEDURE-OPTIONS Set procedure attributes ").
If the default values from the syntax files are to be adopted for a procedure, the procedure head must begin with a SET-PROCEDURE-OPTIONS command with no operand values. This is followed by any required procedure parameter declarations.
If the SDF-P-specific default values are to be adopted for the procedure, the SET-PROCEDURE-OPTIONS command must be omitted. If procedure parameters are to be declared, the procedure head then begins with the declaration of these parameters. If no procedure parameters are to be declared, the procedure begins with the first command of the procedure body. The procedure head is then considered to be implicitly declared.
SDF V4.1 permits task-specific default values to be defined. Although these default values may be defined in S procedures, they take effect with interactive input only. They are ignored in procedure mode; in this mode, the default values set in the syntax files apply. Task-specific default values must not be specified in control flow commands nor in the procedure head. The manual “SDF Introductory Guide” [20] contains more information about task-specific default values.