OSF DCE Application Development Guide--Core Components

OSF DCE Application Development Guide—Core Components
5.6 The Backing Store Routines
Many of the backing store routines appear in three versions: plain, by name, and by
UUID. The plain version will work with backing stores that were created to be indexed
either by name, or by UUID, while the restricted versions accept only the matching type.
It is advantageous to use the restricted versions when they are appropriate because they
provide type checking by the compiler, as well as visual clarity of purpose.
The backing store operations described in the following sections are supported.
5.6.1 Opening a Backing Store
The dce_db_open() routine creates a new backing store or opens an existing one. The
backing store is identified by a filename. There are flags to permit the following choices:
• Create a new backing store or open an existing one.
• Create a new backing store indexed by name or UUID. (The choice depends upon
the server’s purpose.) This index is called the backing store key.
• Open an existing backing store read/write or read-only.
• Use the standard header or not.
Every backing store is created with one of the two possible index schemes, by name or
by UUID, and you cannot subsequently open it for use with the other scheme. Also,
once a backing store has been created with (or without) standard headers, you cannot
subsequently open it the other way.
The routine returns a handle by which subsequent operations identify the backing store.
The following conventions for filenames are recommended:
xxx .acl ACL storage.
xxx .db Backing store filename.
5.6.2 Closing a Backing Store
The dce_db_close() routine frees the handle. It closes any open files and releases all
other resources associated with the backing store.
5.6.3 Storing or Retrieving Data
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