|STRFTIME(3)||Library Functions Manual||STRFTIME(3)|
strftime — format
date and time
maxsize, const char
*format, const struct tm
strftime() function formats the
information from timeptr (as described in
mktime(3)) into the buffer
buf according to the string pointed to by
The format string consists of zero or more
conversion specifications and ordinary characters. All ordinary characters
are copied directly into the buffer. A conversion specification consists of
a percent sign ‘
%’ and one other
No more than maxsize characters will be placed into the array.
Each conversion specification is replaced by the characters as follows which are then copied into the buffer.
+HHMM” or “
-HHMM” as appropriate, with positive values representing locations east of Greenwich, or by the empty string if this is not determinable.
If the total number of resulting characters, including the
terminating NUL character, is not more than maxsize,
strftime() returns the number of characters placed
in the array, not counting the terminating NUL. Otherwise, zero is
strftime() function conforms to
ISO/IEC 9899:1999 (“ISO C99”),
except that the ‘
O’ conversion modifiers are ignored
by this implementation.
%+’ conversion specifications are
Use of the ISO 8601 conversions may produce non-intuitive results. Week 01 of a year is per definition the first week which has the Thursday in this year, which is equivalent to the week which contains the fourth day of January. In other words, the first week of a new year is the week which has the majority of its days in the new year. Week 01 might also contain days from the previous year and the week before week 01 of a year is the last week (52 or 53) of the previous year even if it contains days from the new year. A week starts with Monday (day 1) and ends with Sunday (day 7). For example, the first week of the year 1997 lasts from 1996-12-30 to 1997-01-05.
A predecessor to
ptime(), first appeared in
Version 1 AT&T UNIX. The
strftime() function has been available since
Keith Bostic implemented the
BSD version of
There is no conversion specification for the phase of the moon.
Note that while this implementation of
strftime() will always NUL terminate
buf, other implementations may not do so when
maxsize is not large enough to store the entire time
string. The contents of buf are implementation
specific in this case.
|February 8, 2016||OpenBSD-6.0|