DBCLINIC.BAS

       A UTILITY PROGRAM FOR dBASEII (tm) FILE MAINTENANCE


DESCRIPTION

The "Data Base Clinic" is a handy utility to have around when 
working with data base files with extension type .DBF or .TXT but 
of unknown or questionable size or integrity.  It can display 
Structure header information from .DBF files or count the actual 
number of records they contain and allow you to change the record 
count and/or "last update" date.  It can also find the record 
lengths and number of records in .TXT files.  It is written in 
Microsoft's BASIC-80 (tm) (the Disk MBASIC (tm) for CP/M)(tm), 
Version 5.x, and is menu driven and fully prompting.  The program 
contains five Wards, or modes of operation:

WARD-A:   This portion of the program displays the Record Length 
          of a given .DBF or .TXT file.  With .DBF files, it gets 
          this information from the file Structure header.  With 
          .TXT files, it actually samples the file and checks the 
          length of the first record (up to 1000 characters--the 
          dBASEII (tm) limit for record length).

WARD-B:   Ward-B displays the actual Structure header information 
          from any .DBF file in the .LIST STRUCture format of 
          dBASEII (tm).  This Ward is only available to .DBF files, 
          since .TXT files do not have file Structure headers.  
          Note that, although this is a quick way of finding out 
          how large a file is, in terms of numbers of records, 
          there are times when the number can become corrupted, so 
          that it is actually smaller than it should be--as when a 
          power glitch or computer hangup requires a RESET or re-
          boot, leaving the header information un-updated.  Any time
          a file is not closed by QUITing, this can occur.  In such
          a case, a visit to Wards C and D is in order.

WARD-C:   This is the heart of the program!  In this Ward, you 
          can actually get an exact count of the number of 
          records a data base file contains.  It uses a binary 
          search pattern to find the end of the file very 
          quickly, and then backs off 2K bytes and counts to the 
          end of the file.  A final count is usually displayed 
          within 10 seconds or less.  The program limits out at 
          32,767 x 128 bytes (that's 4-megabytes!!--which should 
          cause no problems to the average user).  This Ward is 
          open to both .DBF and .TXT file types.

WARD-D:   This Ward is for displaying and changing the Record 
          Count in a file's Structure header, if it happens to be 
          different from the count obtained in Ward-C; a handy 
          tool when the header becomes corrupted, since Sorting and 
          Indexing won't work correctly until the number of re-
          cords in the header is correct.  If you make a mistake
          in your entry, use the BACKSPACE key to rub out to the
          last good digit and reenter.  THE MAXIMUM NUMBER THAT 
          CAN BE ENTERED IS 32,767, because of MBASIC's integer 
          limits.  But then, who has database files over 32,767 
          records long?  This Ward is only for .DBF files.

WARD-E:   This Ward allows the Last Update date to be displayed 
          from the file's header and changed.  Suppose you en-
          tered dBASEII (tm) with a 00/00/00 (no entry) date and 
          later thought better about it.  You can easily correct 
          the header date, using Ward E.  Your entry will auto-
          matically be accepted, updated, and verified after the 
          sixth digit is typed in.  You won't have to type in 
          "/" month-day-year separators, nor will they even be
          accepted.  Prior to keying in the last digit, if you
          have made a mistake, hit the BACKSPACE key once to 
          clear your entire entry so you can begin again.


USING THE PROGRAM

As mentioned at the start, the program is menu driven and fully 
prompting.  You just can't make a mistake (well, almost).  It 
will not accept a file name without a .DBF or .TXT extension or 
one with a disk drive designation higher than D: (highest drive 
is easily changed, however).  If you find yourself in a situation 
where you don't know what file name to enter, just enter DIR to 
get a Directory of your disk.  Also, if you are in Wards D or E 
and decide that you don't want to change the file header after 
all, simply reenter the same record count or date that is being 
displayed.

One more thing!  If you insert a new disk at any time, you should
immediately "Reset" the program.  This is done by entering a "null" 
filename at the "ENTER FILENAME (DIR=DIRECTORY):" prompt; that is, 
by simply pressing the carriage RETURN key before any other charac-
ter.  The only response you'll notice is some disk drive activity.  
Failure to do this will get you a "Bdos Error: Drive $R/O" error 
from CP/M (tm) in Ward D or E, when the program attempts to write 
the update information back to the file header.

In its present form, this program WILL NOT compile under BASCOM 
(tm), due mainly to the use of unusually long variable names.  
It has some other serious problems as well.  Ask me about them!!
Except for a speed-up in program loading, there would be no real 
advantage to compiling, since all significant runtime delays occur 
because of disk accessing, and there is no way to speed that up.

Please enjoy this utility!

                              Dick Bollinger


    (P.S. This program has been tested on both floppy and hard
          disk drives!  But if you do find a bug in the program, 
          I'd appreciate it if you would please leave me a mes-
          sage on Stu's RBBS; phone [714] 599-2109; giving full 
          details: Ward you were in, file record length, number 
          of records, ERR and ERL numbers, what happened, etc.
          I'll get back to you; that's a promise.)

(tm) "dBASEII" is a trademark of Ashton-Tate
     "BASIC-80","MBASIC", and "BASCOM" are trademarks of Microsoft
     "CP/M" is a trademark of Digital Research