The PC-SIG Library 10/The PC-Sig Library - Shareware for the IBM PC and Compatibles (PC-SIG)(Tenth Edition Disks 1-2804)(1991).iso/PC_SIGCD/19/9/DISK1997.ZIP/PMCTIPS.DOC

Text File | 1989-11-12 | 7KB | 149 lines

                                     PMCAT+

                     Tips and Hints and General Information


        General Information:

            PMCAT+ is a 'disk file catalog' program.  When we first
            designed PMCAT+, the concept we had of a disk file catalog
            was a program that cataloged the programs on floppy disks
            only.  In the last two years, it has become increasingly
            apparent that many, if not most, users consider hard
            drives to belong in the realm of things a disk file cat-
            alog ought to deal with...and that is a very reasonable
            expectation.

            On the other hand, there were and still are some excellent
            programs I prefer to call 'file management' utilities,
            such as Xtree.  These file management programs have the
            ability to copy, move and even edit files, but don't
            perform the cataloging functions of a program like PMCAT+.

            In short, PMCAT+ is designed to allow you to do pretty much
            whatever you want to do with file information DOS stores
            in the directories of a disk or diskette.  When you need
            to work on the physical file itself, you must either use
            one of the file managers, or the DOS shell of PMCAT+ and
            then do whatever you need through the shell, at the
            command line prompt.  You may, however, read the contents
            of files using PMCAT+ in conjunction with a file lister
            and de-archiving (if the file is within an archive)
            utility.

            Despair not, however.  We are working on a program to
            incorporate the best of both worlds, file managers and
            file catalogers.  Keep an eye out for it.  It will be a
            product of Hip Pocket Software.


        Technical Information about PMCAT+:

            PMCAT+ stores files in memory as it reads them, in the form
            of a 'linked list' of files.  The CATALOG is the root or
            'parent' of every volume contained within that catalog.
            Each volume contained within the CATALOG is a 'child' of
            the parent CATALOG.  Each directory in the root directory
            of each volume is a parent to the files contained within
            the specific directory and so on.  Therefore, each file
            and directory has 'pointers' (an address of 4 bytes, in
            RAM, which tells PMCAT+ where the record for that file or
            directory is, physically).  Every record (file, volume,
            catalog) has pointers as a portion of itself which tell
            where and what its parent is, what and where its children
            are, and what and where its peers (a 'next' pointer to a
            file, directory or volume that has the same parent) are.

            Without going into too much more detail, you can know that
            each file read into PMCAT+ will occupy 38 bytes of memory
            plus the string representing each directory and/or
            subdirectory.  A good rule of thumb is about 45 bytes per
            entry on the average. If you comment a file, then add
            another 80 bytes to this requirement (per file commented).

            The alogrithm (sequence of processing steps) we use to
            link new files into the list automatically sorts files
            having the same parent.  This isn't apparent when you View
            the complete catalog unless you open the Infowindow and
            look at the path to the files.

            As you add comments to files that already exist in PMCAT+,
            the amount of memory required increases by up to 81
            characters per file (depending on how long your comment
            is).

            A practical technical limit for a machine with 500K
            available for cataloging is about 10,000 files.  If fully
            commented (every file contains an 80 character comment),
            the limit is about 3000 files.



        Hints and Tips:


            ARCHIVES -

            Although PMCAT+ has the ability to read the contents
            (directories) of ARC, ZIP ,LZH and PAK files, that process
            may be found to be interesting at first and inconvenient (in
            terms of memory use) later.  In most applications, the name
            of the compressed file indicates the overall function of the
            support and executable files contained within it. If you
            start by cataloging *every* file by using the features that
            read directories of compressed file format and later decide
            you wish you hadn't, a simple update by rereading the disk
            with the archive reading turned off will fix things.

            A good alternative to the above is to read your disks with
            archive reading turned on and the masking feature also
            active to get only the FILENAME.EXT's that you want.


            MULTIPLE CATALOGS -

            Although PMCAT+ was originally intended to be used with
            small to moderate (50 - 200 diskettes) catalogs, it is
            quite capable of managing truly huge diskette collections.

            For some the idea of splitting a collection into separate
            files is abhorent, for others it seems to make a great
            deal of sense.  The purpose of this is not to judge or
            offer opinions about how you should manage things, but
            rather to show how PMCAT+ *can* do it.

            We've had a number of requests to offer an option called
            'categories' to PMCAT+.  Given the fact that a simple word
            or indentifier in the comments section of a file record
            can accomplish that task, or the ease with which a
            different catalog can be loaded, we haven't *yet* done
            that particular update.  (The coding of the option would
            require the user to evaluate each file as it is read and
            that particular process is something we've tried very hard
            to avoid to date).  We would appreciate comments on how
            you would like to see the 'categories' feature implemented
            if we should go ahead with it.

            At any rate, splitting your collection into GAMES, UTILS,
            APPLICATIONS, etc., would allow PMCAT+ to work with your
            collection without hesitation.  We prefer the speed of
            PMCAT+ to be fully available at all times.  Obviously, if
            our users would rather have a huge catalog held on disk
            and accessed more slowly, we would be remiss in not
            addressing that request.


            SEARCHING FILENAMES AND COMMENTS -

            This newest version of PMCAT+ has had some surgery done on
            its searching routines ... for the better, we think.
            Wildcards, ('*' represents any number of characters of any
            form, '?' represents any single character of any form) may
            be used in your search of filenames or comments.  The
            search is now consistent in both areas due to improvements
            in the speed of 'parsing' (looking through the files and
            comments).