|  | 
        A type X meets the IoControlCommand requirements if it satisfies
        the requirements listed below.
      
        In the table below, a denotes
        a (possibly const) value of type X,
        and b denotes a value of
        type X.
      
Table 22. IoControlCommand requirements for extensible implementations
| expression | type | 
                  assertion/note | 
|---|---|---|
| 
                   | 
                   | 
                  Returns a value suitable for passing as the request
                  argument to POSIX  | 
| 
                   | 
                   |