Get the weekday from a date

If you need something more robust or wish to use built-in Windows commands, here's an example:

;.lib "Kernel32.dll"
;GetDate%(iLocale%, iFlags%, iDate%, iFormat$, oDate$, iSizeBuf%):"GetDateFormatA"
;GetDateAny%(locale%, dwFlags%, lpDate*, lpFormat$, lpDateStr$, size%):"GetDateFormatA"

day$ = String(" ", 150)
GetDate(0, 0, 0, "d dd ddd dddd M MM MMM MMMM y yy yyyy gg", day, Len(day))
Print day

time = CreateBank(16)
PokeShort(time, 0, 2004) ; Year
PokeShort(time, 2, 4) ; Month
PokeShort(time, 6, 17) ; Day
GetDateAny(0, 0, time, "ddd MM-dd-yy", day, Len(day))
Print day