STRFTIME

NAME

SYNOPSIS

#include <sys/types.h>
#include <time.h>

size_t strftime(char *s, size_t maxsize, const char *format,
        const struct tm *timeptr);

DESCRIPTION

``The strftime function places characters into the array pointed to by s as controlled by the string pointed to by format. The format shall be a multibyte character sequence, beginning and ending in its initial shift state. The format string consists of zero or more conversion specifiers and ordinary multibyte characters. A conversion specifier consists of a % character, possibly followed by an E or O modifier character (described below), followed by a character that determines the behavior of the conversion specifier. All ordinary multibyte characters (including the terminating null character) are copied unchanged into the array. If copying takes place between objects that overlap the behavior is undefined. No more than maxsize characters are placed into the array.

``Each conversion specifier is replaced by appropriate characters as described in the following list. The appropriate characters are determined by the LC_TIME category of the current locale and by the values of zero or more members of the broken-down time structure pointed to by timeptr, as specified by brackets in the description. If any of the specified values is outside the normal range, the characters stored are unspecified.''

%a

is replaced by the locale's abbreviated weekday name.

%A

is replaced by the locale's full weekday name.

%b

is replaced by the locale's abbreviated month name.

%B

is replaced by the locale's full month name.

%c

is replaced by the locale's appropriate date and time representation. (This is %A %B %d %T %Y in the "C" locale.)

%C

is replaced by the 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.

%e

is replaced by the day of the month as a decimal number (1-31); a single digit is preceded by a space.

%F

is equivalent to %Y-%m-%d (the ISO 8601 date format).

%g

is replaced by the year without century of the ISO week number as a decimal number (00-99).

%G

is replaced by the year with century of the ISO week number as a decimal number.

%h

is equivalent to %b.

%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).

%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 with a newline character (ASCII LF).

%p

is replaced by the locale's equivalent of the AM/PM designations associated with a 12-hour clock.

%r

is replaced by the locale's 12-hour clock time. (This is %I:%M:%S %p in the "C" locale.)

%R

is equivalent to %H:%M.

%S

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

%t

is replaced with a TAB character.

%T

is equivalent to %H:%M:%S.

%u

is replaced by the ISO 8601 weekday as a decimal number [1 (Monday)-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 ISO 8601 week number of the year (the first Monday as the first day of week 1) as a decimal number (01-53).

%w

is replaced by the weekday as a decimal number [0 (Sunday)-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 appropriate date representation. (This is %A %B %d %Y in the "C" locale.)

%X

is replaced by the locale's appropriate time representation. (This is %T in the "C" locale.)

%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

The timezone offset in a +HHMM format (e.g. the format necessary to produce RFC-822/RFC-1036 date headers).

%Z

is replaced by the time zone name or abbreviation, or by no characters if no time zone is determinable.

%%

is replaced by %.

If a conversion specifier is not one of the above, the behavior is undefined.  

RETURNS

ISO 8601

For example, January 1, 1993, is in week 53 of 1992. Thus, the year of its ISO week number is 1992, even though its year is 1993. Similarly, December 31, 1973, is in week 1 of 1974. Thus, the year of its ISO week number is 1974, even though its year is 1973.  

ALTERNATE REPRESENTATIONS

NON-ISO EXTENSIONS

SunOS Extensions

%k

is replaced by the hour (24-hour clock) as a decimal number (0-23). Single digit numbers are padded with a blank.

%l

is replaced by the hour (12-hour clock) as a decimal number (1-12). Single digit numbers are padded with a blank.

HP/UX Extensions

%N

The ``Emporer/Era'' name. Typically, this is equivalent to the century (same as %C ).

%o

The ``Emporer/Era'' year. Typically, this is equivalent to the year (same as %y ).

VMS Extensions

%v

The date in VMS format (e.g. 20-JUN-1991).

Other Extensions

%s

The time in ``seconds since the Epoch,'' usually Midnight January 1, 1970, UTC.

SEE ALSO

BUGS

The ``appropriate'' values used for %c, %x, are %X are always those specified by the 1999 ISO C standard for the "C" locale.  

CAVEATS

AUTHOR

ACKNOWLEDGEMENTS

Index

NAME

SYNOPSIS

DESCRIPTION

RETURNS

ISO 8601

ALTERNATE REPRESENTATIONS

NON-ISO EXTENSIONS

SunOS Extensions

HP/UX Extensions

VMS Extensions

Other Extensions

SEE ALSO

BUGS

CAVEATS

AUTHOR

ACKNOWLEDGEMENTS