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文字

在头文件<time.h>中定义



time_t time(time_t * arg);



返回编码为time_t对象的当前日历时间,并将其存储在time_t指向的对象中arg(除非arg是空指针)。

参数

ARG

-

指向时间将被存储的time_t对象的指针或空指针

返回值

当前日历时间编码为time_t成功时的对象,(time_t)(-1)错误。如果arg不是空指针,返回值也存储在指向的对象中arg

注释

日历时间的编码time_t是未指定的,但大多数系统符合POSIX规范,并返回一个整数类型的值,它保存自Epoch以来的秒数。time_t2038年的实现中有一个32位有符号整数(许多历史实现)失败。

#include <stdio.h>#include <time.h>#include <stdint.h>
 int main(void){
    time_t result = time(NULL);    if(result != -1)        printf("The current time is %s(%ju seconds since the Epoch)\n",               asctime(gmtime(&result)), (uintmax_t)result);}

可能的输出:

The current time is Fri Apr 24 15:05:25 2015(1429887925 seconds since the Epoch)

参考

  • C11标准(ISO / IEC 9899:2011):

    • 7.27.2.4时间函数(p:391)

  • C99标准(ISO / IEC 9899:1999):

    • 7.23.2.4时间函数(p:341)

  • C89 / C90标准(ISO / IEC 9899:1990):

    • 4.12.2.4时间函数

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