/sys$common/syshlp/helplib.hlb LGI Routines, LGI$ICB_GET_INPUT, Description  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    The LGI$ICB_GET_INPUT callback routine invokes the LOGINOUT input
    routine to enable interaction with character-cell terminal users.
    The read operation provides a timeout to ensure that the UAF
    record does not remain locked if the user presses Ctrl/S.