text: 
  /* $selId: dow.c,v 2.0 1995/10/24 01:13:06 lees Exp $
   * Copyright 1993-1995, Scott E. Lee, all rights reserved.
   * Permission granted to use, copy, modify, distribute and sell so long as
   * the above copyright and this permission statement are retained in all
   * copies.  THERE IS NO WARRANTY - USE AT YOUR OWN RISK.
   *
   * $Id: dow.c,v 1.2 1998/12/28 09:34:47 sas Exp $ 
   */
  
  
  
  /**************************************************************************
   *
   * These are the externally visible components of this file:
   *
   *     int
   *     DayOfWeek(
   *         long int sdn);
   *
   * Convert a SDN to a day-of-week number (0 to 6).  Where 0 stands for
   * Sunday, 1 for Monday, etc. and 6 stands for Saturday.
   *
   *     char *DayNameShort[7];
   *
   * Convert a day-of-week number (0 to 6), as returned from DayOfWeek(), to
   * the abbreviated (three character) name of the day.
   *
   *     char *DayNameLong[7];
   *
   * Convert a day-of-week number (0 to 6), as returned from DayOfWeek(), to
   * the name of the day.
   *
   **************************************************************************/
  
  #include "sdncal.h"
  
  int DayOfWeek(
  				 long int sdn)
  {
  	int dow;
  
  	dow = (sdn + 1) % 7;
  	if (dow >= 0) {
  		return (dow);
  	} else {
  		return (dow + 7);
  	}
  }
  
  char *DayNameShort[7] =
  {
  	"Sun",
  	"Mon",
  	"Tue",
  	"Wed",
  	"Thu",
  	"Fri",
  	"Sat"
  };
  
  char *DayNameLong[7] =
  {
  	"Sunday",
  	"Monday",
  	"Tuesday",
  	"Wednesday",
  	"Thursday",
  	"Friday",
  	"Saturday"
  };
  