Applicable release versions: AP, R83
|Description||description of retrieval/update locks.
Attributes 5 and 6 of file-defining items can contain retrieval and update lock codes respectively. These codes are used to restrict access to certain data files and master dictionaries. Lock codes are sets of characters used as codes. Multiple lock codes are separated by value marks. The first lock code (retrieval or update) in an md or file dictionary must be matched in attribute 6 (key) of the user's item in the users file to allow access to the file or md. If the lock code does not match, access is denied.
Locks can be placed at any file pointer level, system, master dictionary, or dictionary. The system pointer controls access to a master dicitonary; the master dicitonary pointer controls a file dictionary, and a file dictionary pointer controls the data file.
1) In this example, a company has four departments; finance, admin, mis, and ops. Each department is maintained in a separate master dictionary. Users remain attached to a specific master dicitonary, but must be prevented from "q-pointing" or using path names to access files on any other master dicitonary. The following are the locks as they appear in the system-level d-pointers and the user definitions: In the "mds" file: id: finance.mstr admin.mstr mis.mstr ops.mstr 001 d d d d 002 67889 786554 45000 23007 003 11 27 13 11 004 005 finance admin mis ops 006 finance admin mis ops 007 008 009 l l l l 010 10 10 10 10 The following are a few of the users and their locks "keys". user: toms glendaj sama carlak gandalf 006(keys) admin finance mis ops admin]mis]ops Every user is restricted the those files found on the local master dictionary except for "gandalf". He can access files on 3 of the four master dictionaries. 2) Update and retrieval locks can be set for specific files. For this example, two files on the "admin" account must be restricted. The files are called, "payroll" and "reviews". A new category of "supervisor" is added. "supervisor" files are only accessable by users with this key regardless of the host master dicitoinary. On the "admin" account, these pointers define the dictionaries of the files: id: payroll reviews 001 d d 002 56678 344567 003 23 13 004 005 supervisor supervisor 006 supervisor supervisor 007 008 009 l l 010 10 10 "gandalf" is now a supervisor: user: gandalf 006(keys) admin]mis]ops]supervisor Now, "gandalf" can retrieve "payroll" and "reviews" but "toms" is still restricted.