29 Time library [time]

29.15 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); }
The contents of the header <ctime> are the same as the C standard library header <time.h>.235
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
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.