【发布时间】:2011-07-21 12:13:55
【问题描述】:
我是 C 编程的新手。谁能告诉我 C 语言中 localtime() 和 gmtime() 之间的区别是什么?
提前感谢!
【问题讨论】:
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你了解什么是时区吗?
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我喜欢time and date dot com,因为我必须应对全球各地的时间。
我是 C 编程的新手。谁能告诉我 C 语言中 localtime() 和 gmtime() 之间的区别是什么?
提前感谢!
【问题讨论】:
来自“本地时间”:
The gmtime() function converts the calendar time timep to broken-down
time representation, expressed in Coordinated Universal Time (UTC). It
may return NULL when the year does not fit into an integer. The return
value points to a statically allocated struct which might be overwrit‐
ten by subsequent calls to any of the date and time functions. The
gmtime_r() function does the same, but stores the data in a user-sup‐
plied struct.
The localtime() function converts the calendar time timep to broken-
time representation, expressed relative to the user’s specified time‐
zone. The function acts as if it called tzset(3) and sets the external
variables tzname with information about the current timezone, timezone
with the difference between Coordinated Universal Time (UTC) and local
standard time in seconds, and daylight to a non-zero value if daylight
savings time rules apply during some part of the year. The return
value points to a statically allocated struct which might be overwrit‐
ten by subsequent calls to any of the date and time functions. The
localtime_r() function does the same, but stores the data in a user-
supplied struct. It need not set tzname, timezone, and daylight.
【讨论】:
gmtime 采用协调世界时 (UTC),而 localtime 采用您的时区
【讨论】: