Syntax:        TXCLRHMRG()

     Purpose:       Clears the horizontal margins of the logical page.

     Argument:      none

     Returns:        0  Successful
                     1  not successful

     Usage:         TXCLRHMRG() is used to reset the left and right
                    margins. The left margin is set to the left edge
                    of the logical page - column 0 - and the right
                    margin is set to the right edge of the logical
                    page.

     Example:       * Clear left and right margins
                    _ret_code = TXCLRHMRG()

     See Also:      TXLMARGIN(), TXRMARGIN()