Standard library header <ctime>

 

C++

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Utilities library

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Atomic operations library (C++11)

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Filesystem library (C++17)

Technical Specifications

 

Standard Library header files

Language Support
<cstddef> <limits> <climits> <cfloat> <cstdint> <new> <typeinfo> <exception> <ciso646>	<initializer_list> <csignal> <csetjmp> <cstdalign> <cstdarg> <cstdbool> <cstdlib> <ctime>
Diagnostics
<stdexcept> <cassert>	<cerrno> <system_error>
General utilities
<utility> <tuple> <bitset> <memory> <cstdlib> <cstring> <functional>	<type_traits> <ratio> <chrono> <ctime> <scoped_allocator> <typeindex>
Strings
<string> <cctype> <cwctype> <cstring>	<cwchar> <cstdlib> <cuchar>
Localization
<locale> <codecvt> <clocale>

Containers
<array> <deque> <forward_list> <list> <vector>	<map> <set> <unordered_map> <unordered_set> <queue> <stack>
Iterators
<iterator>
Algorithms
<algorithm>	<cstdlib>
Numerics
<cfenv> <complex> <random> <valarray>	<numeric> <cmath> <ctgmath> <cstdlib>
Input/Output
<iosfwd> <iostream> <ios> <streambuf> <istream> <ostream>	<iomanip> <sstream> <fstream> <cstdio> <cinttypes>
Regular expressions
<regex>
Thread support
<thread> <mutex> <atomic>	<shared_mutex> <condition_variable> <future>

 

This header was originally in the C standard library as <time.h>.

This header is part of the C-style date and time library.

Macro Constants

CLOCKS_PER_SEC	number of processor clock ticks per second (macro constant)
NULL	implementation-defined null pointer constant (macro constant)

Types

clock_t	process running time (typedef)
size_t	unsigned integer type returned by the sizeof operator (typedef)
time_t	time since epoch type (typedef)
tm	calendar time type (class)

Functions

Time manipulation
clock	returns raw processor clock time since the program is started (function)
time	returns the current time of the system as time since epoch (function)
difftime	computes the difference between times (function)
Format conversions
ctime	converts a time_t object to a textual representation (function)
asctime	converts a tm object to a textual representation (function)
strftime	converts a tm object to custom textual representation (function)
wcsftime	converts a tm object to custom wide string textual representation (function)
gmtime	converts time since epoch to calendar time expressed as Universal Coordinated Time (function)
localtime	converts time since epoch to calendar time expressed as local time (function)
mktime	converts calendar time to time since epoch (function)