2.11BSD/man/cat3/strftime.0
STRFTIME(3) UNIX Programmer's Manual STRFTIME(3)
NAME
strftime - format date and time
SYNOPSIS
#include <sys/types.h>
#include <time.h>
#include <string.h>
size_t strftime(buf, maxsize, format, timeptr)
char *buf;
size_t maxsize;
char *format;
struct tm *timeptr;
DESCRIPTION
The strftime() function formats the information from _t_i_m_e_p_t_r
into the buffer _b_u_f according to the string pointed to by
_f_o_r_m_a_t.
The _f_o_r_m_a_t string consists of zero or more conversion
specifications and ordinary characters. All ordinary char-
acters are copied directly into the buffer. A conversion
specification consists of a percent sign ``%'' and one other
character.
No more than _m_a_x_s_i_z_e characters will be placed into the
array. If the total number of resulting characters, includ-
ing the terminating null character, is not more than _m_a_x_-
_s_i_z_e, strftime() returns the number of characters in the
array, not counting the terminating null. Otherwise, zero
is returned.
Each conversion specification is replaced by the characters
as follows which are then copied into the buffer.
%A is replaced by the full weekday name.
%a is replaced by the abbreviated weekday name, where
the abbreviation is the first three characters.
%B is replaced by the full month name.
%b or %h
is replaced by the abbreviated month name, where the
abbreviation is the first three characters.
%C is equivalent to ``%a %b %e %H:%M:%S %Y'' (the format
produced by _a_s_c_t_i_m_e(3)).
%c is equivalent to ``%m/%d/%y''.
%D is replaced by the date in the format ``mm/dd/yy''.
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STRFTIME(3) UNIX Programmer's Manual STRFTIME(3)
%d is replaced by the day of the month as a decimal
number (01-31).
%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 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 minute as a decimal number (00-
59).
%m is replaced by the month as a decimal number (01-12).
%n is replaced by a newline.
%p is replaced by either ``AM'' or ``PM'' as appropri-
ate.
%R is equivalent to ``%H:%M''
%r is equivalent to ``%I:%M:%S %p'' .
%t is replaced by a tab.
%S is replaced by the second as a decimal number (00-
60).
%T or %X
is equivalent to "%H:%M:%S" .
%U is replaced by the week number of the year (Sunday as
the first day of the week) as a decimal number (00-
53).
%W is replaced by the week number of the year (Monday as
the first day of the week) as a decimal number (00-
53).
%w is replaced by the weekday (Sunday as the first day
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STRFTIME(3) UNIX Programmer's Manual STRFTIME(3)
of the week) as a decimal number (0-6).
%x is equivalent to ``%m/%d/%y %H:%M:%S'' .
%Y is replaced by the year with century as a decimal
number.
%y is replaced by the year without century as a decimal
number (00-99).
%Z is replaced by the time zone name.
%% is replaced by `%' .
SEE ALSO
_d_a_t_e(1), _c_t_i_m_e(3), _p_r_i_n_t_f(1), _p_r_i_n_t_f(3)
STANDARDS
The strftime() function conforms to ANSI X C3.159-
1989(``ANSI C'').
BUGS
There is no conversion specification for the phase of the
moon.
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