Xinu7/contrib/distodt/man/odtunlock.doc

ODTUNLOCK(1)        UNIX Programmer's Manual         ODTUNLOCK(1)



NNNNAAAAMMMMEEEE
     odtunlock - release lock on a backend machine

SSSSYYYYNNNNOOOOPPPPSSSSIIIISSSS
     ooooddddttttuuuunnnnlllloooocccckkkk [ ----cccc_C_L_A_S_S ] [ ----mmmm_M_A_C_H ] [ ----rrrr ]

DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
     _O_d_t_u_n_l_o_c_k releases the caller's currently reserved SUN, mak-
     ing it available for others to use.  Mutual exclusion locks
     are created automatically by _o_d_t and _d_o_w_n_l_o_a_d, and are
     reported by _b_u_s_e_r_s and _s_t_a_t_u_s.  Reservations may expire
     after some idle time even if _o_d_t_u_n_l_o_c_k is not used.  _O_d_t or
     _d_o_w_n_l_o_a_d may reclaim a backend SUN if the reservation has
     expired.

     Reservations are recorded in two places: once with the BED
     in charge of the specified backend, and once on the user's
     local machine.  The reservation on the BED's frontend is the
     _o_f_f_i_c_i_a_l reservation.  The reservation recorded on the
     user's local machine is simply a _h_i_n_t that tells which back-
     end machine the user _p_r_o_b_a_b_l_y has reserved.  _O_d_t_u_n_l_o_c_k
     removes the reservation on the BED's frontend, however, by
     default it does not remove the local reservation.  The next
     time the user uses _o_d_t or _d_o_w_n_l_o_a_d it will check the local
     reservation and then try to connect to the same backend the
     user used the last time.  If that backend is not available,
     _o_d_t and _d_o_w_n_l_o_a_d will then find a new free backend and
     change the local reservation to the new backend.  The ----rrrr
     argument causes the local reservation to be removed as well
     as the reservation on the BED's frontend.

     Without arguments, _o_d_t_u_n_l_o_c_k removes the reservation on the
     backend machine most recently accessed by the caller.

     Argument ----cccc_C_L_A_S_S can be used to specify a _C_L_A_S_S, in which
     case _o_d_t_u_n_l_o_c_k removes the user's most recently held reser-
     vation in that class.

     Argument ----mmmm_M_A_C_H forces _o_d_t_u_n_l_o_c_k to cancel the reservation
     for machine _M_A_C_H within the selected class.

     Argument ----rrrr removes the local reservation lock.

     Xinu's reservation system is a friendly, cooperative
     mutual-exclusion mechanism.  All software that accesses
     backend SUNs is expected to adhere to the reservation system
     to prevent multiple users from trying to access the same
     machine simultaneously.

FFFFIIIILLLLEEEESSSS
     /tmp/xinu/*   Local lock files. Named by user's login id




Printed 6/8/88                                                  1






ODTUNLOCK(1)        UNIX Programmer's Manual         ODTUNLOCK(1)



SSSSEEEEEEEE AAAALLLLSSSSOOOO
     busers(1), odt(1), download(1)





















































Printed 6/8/88                                                  2