Manipulating User Specifications

A user specification is an efficient encoding of the text of a user name. As described on page , all OS and OSFriends procedures that do local access checking accept a user specification parameter, of type User. The super-user is allowed to supply a non-nil user specification, thereby masquerading as another user. To make the parameter passing across the RPC interface more efficient, the type User is implemented as an opaque ref.

  

PROCEDURE LookUpUser(username: Text.T): User RAISES {};

    LookUpUser converts the text of a user name into a user specification suitable for passing as the euser parameter to an OS or OSFriends procedure. LookUpUser returns NIL if the user name is not known.

 

PROCEDURE GetUserName(user: User): Text.T RAISES {Error};

    GetUserName retrieves the text of a user name from a user specification, or raises InvalidArgumentEC if user is NIL.