An unsigned fullword, set by the assembler, containing the length of the string pointed to by the Ptr to Parm String n field.

The external function should use this length to determine the length of the Parm String n passed by the assembler.

The assembler sets this field to a value between 0 and 1024 inclusive.

The Number of Parameters field indicates the number of Parm String n Length fields in the Request Information List.