30
Time library
[time]
30.15
Header
<ctime>
synopsis
[ctime.syn]
🔗
#define
NULL
see
[support.
types.
nullptr]
#define
CLOCKS_PER_SEC
see below
#define
TIME_UTC
see below
namespace
std
{
using
size_t
=
see
[support.
types.
layout]
;
using
clock_t
=
see below
;
using
time_t
=
see below
;
struct
timespec;
struct
tm; clock_t clock
(
)
;
double
difftime
(
time_t time1, time_t time0
)
; time_t mktime
(
tm
*
timeptr
)
; time_t time
(
time_t
*
timer
)
;
int
timespec_get
(
timespec
*
ts,
int
base
)
;
char
*
asctime
(
const
tm
*
timeptr
)
;
char
*
ctime
(
const
time_t
*
timer
)
; tm
*
gmtime
(
const
time_t
*
timer
)
; tm
*
localtime
(
const
time_t
*
timer
)
; size_t strftime
(
char
*
s, size_t maxsize,
const
char
*
format,
const
tm
*
timeptr
)
;
}
1
#
The contents of the header
<ctime>
are the same as the C standard library header
<time.h>
.
260
2
#
The functions
asctime
,
ctime
,
gmtime
, and
localtime
are not required to avoid data races (
[res.
on.
data.
races]
)
.
See also:
ISO/IEC 9899:2018, 7.27
260)
260)
strftime
supports the C conversion specifiers
C
,
D
,
e
,
F
,
g
,
G
,
h
,
r
,
R
,
t
,
T
,
u
,
V
, and
z
, and the modifiers
E
and
O
.