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When we get date, we receive a WORD value which contains date with year. So Date is stored in 2 bytes. What is range for these 2 bytes? What could be the minimum value and what is maximum value. Is 0x0058 a valid value for date?
Time is also stored in 2 bytes.What is the range for time
What "date" and "time" functions do you mean?
Depends what you are talking about, but if it is the time_t returned by function time(), then this is what cplusplus.com has to say about it:
If you make the assumption that time_t is an integral type (just like size_t), then yes, it is OK.Quote:
Type capable of representing times and support arithmetical operations.
This type is returned by the time function and is used as parameter by some other functions of the <ctime> header.
It is almost universally expected to be an integral value representing the number of seconds elapsed since 00:00 hours, Jan 1, 1970 UTC. This is due to historical reasons, since it corresponds to a unix timestamp, but is widely implemented in C libraries across all platforms.
If you are talking about the tm struct, then it is not OK, as each member should be assigned one by one.
Finally, if you are manipulating any other time type, well I don't have enough details to help.
Seeing that he's using the terminology WORD, I would assume this is some Windows timing structure :P
Usually date and time is stored at a 32 or 64 bit unsigned integer using a UNIX timestamp. On Windows, I have no idea, probably DOS time or VISI time, but if you use the built in C functions, you are guaranteed to get UNIX... *I think*
"guaranteed" is so ambiguous... I think every implementation I know of does it, but the standard does no mandate it...Quote:
Originally Posted by ninja9578
I hate those cases.
No, but the terminology "time_t" comes from UNIX.
Lets consider Windows OS only
FAT file system keeps create date, create time etc for any file in 2 bytes (WORD)
i am talking about the range of these 2 bytes
From MSDN (File Times):See also http://support.microsoft.com/kb/127830Quote:
on Windows NT FAT, create time has a resolution of 10 milliseconds, write time has a resolution of 2 seconds, and access time has a resolution of 1 day (really, the access date). On NTFS, access time has a resolution of 1 hour. Furthermore, FAT records times on disk in local time, while NTFS records times on disk in UTC, so it is not affected by changes in time zone or daylight saving time.
the best way for me to check the range for any time or date is to use the function
which function returns time in 2 bytes. also which function returns date in 2 bytes
It would be better if you had explained what (and what for?) you are trying to achieve with such a function as well as with 2-bytes date and 2-bytes time values.
How many people still use FAT though? The only reason to use FAT is if you dual boot with OSX, as it can't write to NTSF.
See the FAT description in WikiQuote:
Originally Posted by MFCQuery
thanks for giving the wiki page link
i wanted to know about what these 2 bytes contain
wiki page answered this
If you had asked something like "What is the date/time structure of the file in FAT?" or "How is file date/time saved in FAT system?" you would get an answer yesterday! :rolleyes:Quote:
Originally Posted by MFCQuery