VSORT Version 1.0 - Copyright 1989 Roger E. Donais

GENERAL:

VSORT is a DOS Sort Filter with command line format and options similar
to the DOS Sort utility. The input file is expected to be a carriage
return - line feed delimited ascii text file.  Source lines may be
random length, but cannot exceed 4096 characters. Maximum size of file
is typically limimted to the available disk space.

Type VSORT /h to obtain an on-screen command/option summary.

When invoked with no parameters, VSORT will simply sort input from the
standard input device (CON) to the standard output device (CON). To
terminate input, press ^Z (Control plus Z) followed by ENTER.

The sort will *NOT* be attempted if there is than 48k of memory, and
will abort at the end of the first pass if there is insufficient memory
for the merge buffers. The elapsed time to reach this point will depend
on your disk through-put, which is typically 3% longer than the time it
takes to read and write the file in question using a 25 mHz 486 with a
680 Meg ESDI Drive reporting a 16ms access and 1012 Meg transfer rate.

USAGE:

    vsort  <infile  >outfile  [/R] [/+n] [/P<path>]

    where  <infile       is a standard DOS redirected input specification.

           >outfile      is a standard DOS redirected output specification.

           /R            sorts in reverse order (default = ascending)tarting

           /+n           sorts starting at column n (default = column 1)

           /P<path>      is an optional DOS drive/path specification for
                         the intermediate work file.

       NOTE: Vsort uses code page 437 to establish ranking of characters
             and treats upper and lower case letters as equal weight


EXAMPLE:     vsort <e:\test1.txt >temp.txt /PD:\


MESSAGES:

All runtime messages are written to the stderr device, and will, by
default, be directed to the crt display.

When invoked with an /h parameter, VSORT will display a
command-line/option summary.

Additional messages that may be displayed are -

         ** SORT COMMAND ERROR: **
                 indicates an error was detected in the command line.
                 The command line will be displayed with a carat (^)
                 marking the position where the error was detected.

         ** insufficient memory **
                 indicates that there is not enough memory available to
                 provide the necessary merge buffers, or at startup
                 there was less than 48k of memory is available.

         ** unable to create intermediate file **
                 indicates an error occurred when VSORT attempted to
                 create the intermediate work file (SORT0000.$$$).

         ** intermediate file write error **
                 indicates an error occurred when writing to the
                 intermediate work file.

         ** output file write error **
                 indicates an error occurred when writing to the
                 redirected stdout file handle.

SYSTEM REQUIREMENTS:

This release of VSORT was tested using a 9-Meg file consisting of
128,000 seventy (70) character carriage-return line-feed delimited
records.  A TSR was used to consume all but 64k of available memory.

It is extremely difficult to estimate the resources required to sort a
file of variable length lines. However, a general rule of thumb is that
the available free disk space must be at least twice the size of the
original file. This may exist on two separate drives, but each of the
two drives must have free space at least equal to the size of the
original file.

Determing the number of merge blocks, or estimating the memory required
to perform the merge pass is well beyond the scope of this guide.

You will know if the existing resources are sufficient to complete the
sort by the end of the first pass. The elapsed time to reach this point
will depend of your disk through-put, and will usually be only 3% longer
than the time it takes to read and write the file in question. The 3%
factor is based upon tests performed using a 25 mHz 486 and the 16ms
access and 1012 Meg transfer provided by a 680 Meg ESDI Drive.

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                        --- The legal Stuff ---

VSORT includes trade secrets and confidential information, which is the
copyrighted intellectual property of Roger Donais. 

VSORT may be freely copied and distributed on a non-profit basis, but
may not be sold or traded for monetary value, nor used commercially
without the written consent of the author.

VSORT is provided without warranty, expressed or implied, including but
not limited to fitfulness for a particular purpose. The author does not
guarantee the accuracy of the program and accepts no responsibility for
its use.

                Roger Donais (Compuserve ID: 70414,524)