TM(3) BSD Library Functions Manual TM(3)
NAME
tm -- time structure
SYNOPSIS
#include <time.h>
DESCRIPTION
The <time.h> header defines the tm structure that contains calendar dates and time broken down into components. The following standards-com-
pliant fields are present:
Type Field Represents Range
int tm_sec Seconds [0, 61]
int tm_min Minutes [0, 59]
int tm_hour Hours since midnight [0, 23]
int tm_mday Day of the month [1, 31]
int tm_mon Months since January [0, 11]
int tm_year Years since 1900
int tm_wday Days since Sunday [0, 6]
int tm_yday Days since January 1 [0, 365]
int tm_isdt Positive if daylight savings >= 0
The tm structure is used by various common library routines such as mktime(3), localtime(3), and strptime(3). All fields described above are
defined in the IEEE Std 1003.1-2008 (``POSIX.1'') standard.
NetBSD Extensions
In addition, the following NetBSD-specific fields are available:
Type Field Represents
int tm_gmtoff Offset from UTC in seconds
__aconst char tm_zone Timezone abbreviation
The tm_zone and tm_gmtoff fields exist, and are filled in by applicable library routines, only if arrangements to do so were made when the
library containing these functions was created. There is no guarantee that these fields will continue to exist in this form in future
releases of NetBSD.
The tm_gmtoff field denotes the offset (in seconds) of the time represented from UTC, with positive values indicating east of the Prime
Meridian. The tm_zone field will become invalid and point to freed storage if the corresponding struct tm was returned by localtime_rz(3)
and the const timezone_t tz argument has been freed by tzfree(3).
SEE ALSO
asctime(3), offtime(3), timeval(3), wcsftime(3)
STANDARDS
The tm structure conforms to IEEE Std 1003.1-2008 (``POSIX.1'') with respect to the described standard structure members.
BSD
April 14, 2011 BSD
