USAGE
   signed int sccdi2l(
           signed long *date,
           signed int year,
           signed int month,
           signed int day );

PROTOTYPE IN
   sc_clock.h

DESCRIPTION
   sccdi2l converts three integer date values (year, month, and
   day) into a long integer. The integer values are verified to be a
   valid date before conversion.

EXAMPLE
   #include <stdio.h>
   #include <softc.h>
   #include <sc_clock.h>

   void main()
   {
     int year = 1990, month = 5, day = 16;
     long date = 0L;

     scdinit(20,0);
     sccdi2l(&date, year, month, day);
     printf("%d %d %d = %ld\n", year, month, day, date);
     scdterm();
   }