%a    is replaced by the locale's abbreviated weekday name.  In the de-
           fault locale, it is equivalent to one of the following: ``Sun'',
           ``Mon'', ``Tue'', ``Wed'', ``Thu'', ``Fri'' or ``Sat''.

     %A    is replaced by the locale's full weekday name.  In the default lo-
           cale, it is equivalent to one of the following: ``Sunday'',
           ``Monday'', ``Tuesday'', ``Wednesday'', ``Thursday'', ``Friday'',
           or ``Saturday''.

     %b    is replaced by the locale's abbreviated month name.  In the default
           locale, it is equivalent to one of the following: ``Jan'', ``Feb'',
           ``Mar'', ``Apr'', ``May'', ``Jun'', ``Jul'', ``Aug'', ``Sep'',
           ``Oct'', ``Nov'' or ``Dec''.

     %B    is replaced by the locale's full month name.  In the default lo-
           cale, it is equivalent to one of the following: ``January'',
           ``February'', ``March'', ``April'', ``May'', ``June'', ``July'',
           ``August'', ``September'', ``October'', ``November'' or
           ``December''.

     %c    is replaced by the locale's date and time representation.  In the
           default locale, it is equivalent to ``%x %X'', i.e., ``mm/dd/yy
           hh:mm:ss''.

     %C    is replaced by the century (a year divided by 100 and truncated to
           an integer) as a decimal number (00-99).

     %d    is replaced by the day of the month as a decimal number (01-31).

     %D    is equivalent to ``%m/%d/%y'', i.e ``mm/dd/yy''.

     %e    is replaced by the day of month as a decimal number (1-31); single
           digits are preceded by a blank.

     %h    is replaced by the locale's abbreviated month name.  In the default
           locale, it is equivalent to one of the following: ``Jan'', ``Feb'',
           ``Mar'', ``Apr'', ``May'', ``Jun'', ``Jul'', ``Aug'', ``Sep'',
           ``Oct'', ``Nov'' or ``Dec''.

     %H    is replaced by the hour (24-hour clock) as a decimal number
           (00-23).

     %I    is replaced by the hour (12-hour clock) as a decimal number
           (01-12).

     %j    is replaced by the day of the year as a decimal number (001-366).

     %k    is replaced by the hour (24-hour clock) as a decimal number (0-23);
           single digits are preceded by a blank.

     %l    is replaced by the hour (12-hour clock) as a decimal number (1-12);
           single digits are preceded by a blank.

     %m    is replaced by the month as a decimal number (01-12).

     %M    is replaced by the minute as a decimal number (00-59).

     %n    is replaced by a newline.

     %p    is replaced by locale's equivalent of ``AM'' (ante meridiem) or
           ``PM'' (post meridiem) as appropriate.  In the default locale, it
           is replaced by ``AM'' or ``PM''.

     %r    is equivalent to ``%I:%M:%S %p'', i.e., ``hh:mm:ss AM|PM''.

     %R    is equivalent to ``%H:%M'', i.e., ``hh:mm''.

     %s    is replaced by the number of seconds since the Epoch, UCT (see
           mktime(3)).

     %S    is replaced by the second as a decimal number (00-60).

     %t    is replaced by a tab.

     %T    is equivalent to ``%H:%M:%S'', i.e., ``hh:mm:ss''.

     %u    is replaced by the weekday (Monday as the first day of the week) as
           a decimal number (1-7).

     %U    is replaced by the week number of the year (the first Sunday as the
           first day of week 1) as a decimal number (00-53).

     %V    is replaced by the week number of the year (the first Monday as the
           first day of week 1) as a decimal number (00-53).

     %w    is replaced by the weekday (Sunday as the first day of the week) as
           a decimal number (0-6).

     %W    is replaced by the week number of the year (the first Monday as the
           first day of week 1) as a decimal number (00-53).

     %x    is replaced by the locale's date representation.  In the default
           locale, it is equivalent to ``%m/%d/%y'', i.e., ``mm/dd/yy''.

     %X    is replaced by the locale's time representation.  In the default
           locale, it is equivalent to ``%H:%M:%S'', i.e., ``hh:mm:ss''.

     %y    is replaced by the year without century as a decimal number
           (00-99).


     %Y    is replaced by the year with century as a decimal number.

     %Z    is replaced by the time zone name.

     %%    is replaced by a single % character.