Page 98 - slides.dvi
P. 98

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                                                   4.
                   1.
                                                              2.
                                                        3.
                                –
              2.
                                                                   1.
                                                                                                               File
   Operating
                                                              if
                                       Once
                                             Create
                                                              all
                                                        copy
                   copy
                         Closing
   Systems
                                             a
                                                                         Opening
                                                   create
                         a
                                various
   —
                                                                         a
                                       have
                                                        file
                                                                   directory
              invalidate
                                                              goes
                                             new
                   [new]
                                                   new
                         file:
                                                                         file:
   Filesystem
                                       UFID
                                modes
                   file
                                                                                                               Operations
                                                              well,
                                             file:
              UFID
                                                        control
                                                                   service
                                                   UFID
                                       can
                                                                         UFID
                                (see
                                                                                                               (I)
   Interface
                         status
                                                                         =
                                                   and
                                             UFID
                   control
                         =
                                                        block
                                                                                          4
                                                                                                    1
                                                                                             3
                                                                                                2
                                                                                                        UFID
                                             =
                                       read,
                                next
                                                              eventually
                                                        into
                                                                   recursively
                                                   return
                   block
                                                                                                        SFID
                                                                                             10532
                                                                                          7122
                                                                                                    23421
                                                                                                3250
                                                              get
                                slide)
                                       write,
                                                   to
                   back
                                       etc.
                                                              SFID
                                                        memory.
                                                                   searches
                   to
                         close(UFID)
                                                   caller.
                                                              of
                                                                   for
                   disk.
                                                              file.
                                                                         open(<pathname>)
                                             create(<pathname>)
                                                                                          "              "
                                                                                             "              "
                                                                                                "              "
                                                                   components
                                                                                                        File Control Block (Copy)
                                                                   of
                                                                                                    location on disk, size,...
                                                                   <pathname>
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