The Enable Unsolicited Input routine detects unsolicited input
    and calls an AST routine in response.

    Format

      SMG$ENABLE_UNSOLICITED_INPUT  pasteboard-id ,AST-routine

                                    [,AST-argument]

1  –  Returns

    OpenVMS usage:cond_value
    type:         longword (unsigned)
    access:       write only
    mechanism:    by value

2  –  Arguments

 pasteboard-id

    OpenVMS usage:identifier
    type:         longword (unsigned)
    access:       read only
    mechanism:    by reference

    Specifies the pasteboard for which unsolicited input is being
    enabled. The pasteboard-id argument is the address of an unsigned
    longword that contains the pasteboard identifier.

    The pasteboard identifier is returned by SMG$CREATE_VIRTUAL_
    PASTEBOARD.

 AST-routine

    OpenVMS usage:ast_procedure
    type:         procedure value
    access:       read only
    mechanism:    by value

    AST routine to be called upon receipt of unsolicited input at
    the terminal. The AST-routine argument contains the routine's
    procedure value. SMG$ENABLE_UNSOLICITED_INPUT detects the
    presence of unsolicited input and calls the AST routine with
    six arguments: the pasteboard-id, the AST-argument, R0, R1, PC,
    and PSL (on VAX systems) or PS (on Alpha systems).

 AST-argument

    OpenVMS usage:user_arg
    type:         longword (unsigned)
    access:       read only
    mechanism:    by value

    A value to be passed to the AST routine. The AST-argument
    argument contains the value to be passed to the AST routine.