OS()
 Return the operating system name
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 Syntax

     OS() --> cOsName

 Returns

     OS() returns the operating system name as a character string.

 Description

     OS() is an environment function that returns the name of the disk
     operating system under which the current workstation is operating.  The
     name is returned in the form of the operating system name followed by
     the version number.

 Examples

     .  This example uses OS() to report the operating system under
        which the current workstation is running:

        ? OS()                  // Result: DOS 6.0

 Files   Library is CLIPPER.LIB.