Formats universal dates using the same format specifiers as NSDateFormatter. The format is: %% - A '%' character %a - Abbreviated weekday name %A - Full weekday name %b - Abbreviated month name %B - Full month name %c - Shorthand for “%X %x”, the locale format for date and time %d - Day of the month as a decimal number [01-31] %e - Same as %d but does not print the leading 0 for days 1 through 9 [unlike strftime[], does not print a leading space] %F - Milliseconds as a decimal number [000-999] %H - Hour based on a 24-hour clock as a decimal number [00-23] %I - Hour based on a 12-hour clock as a decimal number [01-12] %j - Day of the year as a decimal number [001-366] %m - Month as a decimal number [01-12] %M - Minute as a decimal number [00-59] %p - AM/PM designation for the locale %S - Second as a decimal number [00-59] %w - Weekday as a decimal number [0-6], where Sunday is 0 %x - Date using the date representation for the locale, including the time zone [produces different results from strftime[]] %X - Time using the time representation for the locale [produces different results from strftime[]] %y - Year without century [00-99] %Y - Year with century [such as 1990] %Z - Time zone name [such as Pacific Daylight Time; produces different results from strftime[]] %z - Time zone offset in hours and minutes from GMT [HHMM] None of %c, %F, %p, %x, %X, %Z, %z are implemented.