6、C与Objective-C编程入门：时间处理、内存管理与对象操作

C与Objective-C编程入门：时间处理、内存管理与对象操作

1. C语言中的时间处理

在C编程中， struct tm 结构体用于将时间分解为各个组成部分，其定义如下：

struct tm {
    int    tm_sec;     /* seconds after the minute [0-60] */
    int    tm_min;     /* minutes after the hour [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_isdst;   /* Daylight Savings Time flag */
    long   tm_gmtoff;  /* offset from CUT in seconds */
    char   *tm_zone;   /* timezone abbreviation */
};