destination-string

    OpenVMS usage:char_string
    type:         character string
    access:       write only
    mechanism:    by descriptor

    Destination string into which STR$UPCASE writes the string it has
    converted to uppercase. The destination-string argument is the
    address of a descriptor pointing to the destination string.

 source-string

    OpenVMS usage:char_string
    type:         character string
    access:       read only
    mechanism:    by descriptor

    Source string that STR$UPCASE converts to uppercase. The source-
    string argument is the address of a descriptor pointing to the
    source string.