On 09/05/2026 00:50, Bruno Haible via GNU coreutils Bug Reports wrote:
Pádraig Brady wrote:
FORMAT Example Description
%% % a literal %
%a Sun locale's abbreviated weekday name
%A Sunday locale's full weekday name
%b Mar locale's abbreviated month name
%B March locale's full month name
%c '%a %x %X' locale's date and time
%C 20 century; like %Y, except omit last two digits
%d 01 day of month
%D 12/31/99 date (ambiguous); same as %m/%d/%y
%e 1 day of month, space padded; same as %_d
%F 1999-12-31 full date; like %+4Y-%m-%d
%g 99 year of ISO week number (last two digits; 00-99); see %G
%G 1999 year of ISO week number; normally useful only with %V
%h Mar same as %b
%H 23 hour (00..23)
%I 01 hour (01..12)
%j 365 day of year (001..366)
%k 8 hour, space padded ( 0..23); same as %_H
%l 9 hour, space padded ( 1..12); same as %_I
%m 12 month (01..12)
%M 59 minute (00..59)
%n \n a newline
%N 123456789 nanoseconds (000000000..999999999)
%p PM locale's equivalent of AM or PM; blank if not known
%P pm like %p, but lower case
%q 4 quarter of year (1..4)
%r 1:11:04 PM locale's 12-hour clock time
%R 23:59 24-hour hour and minute; same as %H:%M
%s 1778169005 seconds since the Epoch (1970-01-01 00:00 UTC)
%S 59 second (00..60)
%t \t a tab
%T 23:59:59 time; same as %H:%M:%S
%u 7 day of week (1..7); 1 is Monday
%U 52 week number of year; Sunday as first day of week (00..53)
%V 52 ISO week number; Monday as first day of week (01..53)
%W 52 week number of year; Monday as first day of week (00..53)
%w 6 day of week (0..6); 0 is Sunday
%x 12/31/99 locale's date (can be ambiguous)
%X 23:59:59 locale's time representation
%y 99 year (last two digits; 00..99)
%Y 1999 year
%z +0400 +hhmm numeric time zone
%:z +04:00 +hh:mm numeric time zone
%::z +04:00:00 +hh:mm:ss numeric time zone
%:::z +04 numeric time zone to necessary precision; with :
%Z EDT alphabetic time zone abbreviation
That's too many lines to search for. As a user, typically I ask:
1) I have a day to display; which directive can I use for it?
2) I have a time to display; which directive can I use for it?
Accordingly, I suggest to split this table into several smaller ones,
namely one for each of:
- literal characters,
- date
- time
- date and time
- time zone
- nanosecond
(similar to what I did in gnulib/lib/strftime.h).
Yes I suppose alphabetic is arbitrary.
I.e. users generally want to know "what letter corresponds to ...",
not "what corresponds to letter .".
cheers,
Padraig
