Edit AllPages

I need to be able to convert from an NSDate to a Windows FILETIME struct. I get the timeintervalsince1970, and then run it through this function, which is supposed to work (got it from the MS website).

FILETIME UnixTimeToFILETIME(time_t t) {

long long int ll;
ll = ((long long)t * 1000000LL);
ll += 116444736000000000LL;
retf.dwHighDateTime = ll >> 32;

retf.dwLowDateTime = ll & 0x00000000FFFFFFFF;
return retf; }

The reverse function, which gets a unix time from FILETIME, is this: (and works fine)

time_t FILETIMEToUnixTime(FILETIME filetime) { long long int t = filetime.dwHighDateTime; t «= 32; t += (unsigned long)filetime.dwLowDateTime; t -= 116444736000000000LL;

return t / 10000000;


I can’t seem to figure out the problem, unless I’m not getting a valid NSDate from the NSFileManager. (Which I am)

Multiply by 10000000, not 1000000?

The version that I found on Microsoft’s support site does this.

void UnixTimeToFileTime(time_t t, LPFILETIME pft) { // Note that LONGLONG is a 64-bit value LONGLONG ll;

ll = Int32x32To64(t, 10000000) + 116444736000000000; pft->dwLowDateTime = (DWORD)ll; pft->dwHighDateTime = ll » 32; }

Also take care to adjust the byte ordering if you plan to read this structure on/from an x86.