VOLSERIAL()
 Determines the DOS disk serial number
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 Syntax

     VOLSERIAL([<cDrive>]) --> nVolSerial

 Argument

     <cDrive>  Designates the drive whose volume serial number is
     queried.  The default is the current disk drive.

 Returns

     VOLSERIAL() returns the volume serial number of the DOS  disk, hard
     disk, or a 0, when you are not dealing with a DOS 4.0 or higher disk
     (see Notes).  When the current drive is unavailable, it returns -1.

 Description

     VOLUME SERIAL NUMBER
     Beginning with DOS version 4.0, every floppy or hard disk receives a
     volume serial number during formatting.  This is a 32-bit number is
     created by DOS using the date, clock time, and a counter.

 Notes

     .  Incompatibilities are possible.

     .  The function always returns a value from the disk parameter
        block of a floppy or hard disk.  Based on the Microsoft
        recommendation for DOS versions prior to 4.0, a value of 0 is
        returned.

 Example

     Query the volume serial number:

     ? VOLSERIAL()            // 0, when no DOS 4.x disk