Returns a command line parameter
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 Syntax

        GT_environ(<nPos>) --> cVar

 Arguments:

      <nPos>  -   The position in the environment list

 Returns:

      cVar    -   The environment variable

 Description:

     Get an environment variable specified by it's position in the
     environ table by reading the C startup variables

 Examples:

      local i

      for i := 0 to GT_EnvCount()
          ? GT_Environ(i)
      next
  $CAVEATS$
      Does not check <nPos> is a valid position in the list.

 Source: ENVIRON.C

 Author:  Andy M Leighton