🚀 go-pugleaf

JF Jolin wrote:
> Here is the scenario:
> 
> hFile = CreateFile( lpszFileName, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL );
> 
> SetFileTime( hFile, &fTimeCreate, &fTimeLastAccess, &fTimeLastWrite );
> 
> CloseHandle( hFile );
> 
> 
> Whatever time is specified in fTimeLastAccess, that will be overwritten when CloseHandle instruction will be executed.

MSDN that states : "lpLastAccessTime
[in] A pointer to a FILETIME structure that contains the new date and 
time the file was last accessed. The last access time includes the last 
time the file was written to, read from, or (in the case of executable 
files) run. This parameter can be NULL if the application does not need 
to set this information."
And now the crucial line:
"To preserve the existing last access time for a file even after 
accessing a file, call SetFileTime with this parameter set to -1 before 
closing the file handle."

Here is the working sample:

#include <windows.h>
#include <string>
#include <iostream>
#include <ctime>

//Important kb about converting time
//http://support.microsoft.com/kb/167296

void UnixTimeToFileTime(std::time_t t, LPFILETIME pft)
{
  LONGLONG ll = Int32x32To64(t, 10000000) + 116444736000000000i64;
  pft->dwLowDateTime = (DWORD)ll;
  pft->dwHighDateTime = ll >> 32;
}

void changeFileTime(const std::string &fname) {

  HANDLE hFile = CreateFile( fname.c_str(),
                             GENERIC_READ | GENERIC_WRITE,
                             0,
                             NULL,
                             OPEN_EXISTING,
                             FILE_ATTRIBUTE_NORMAL,
                             NULL );
  if (hFile != INVALID_HANDLE_VALUE){
    FILETIME ft = {0UL}, ftminus = {-1L,-1L};
    std::tm tmp = {0,0,14,7,3,2007 - 1900,0,0,0};
    std::time_t timeValue = std::mktime(&tmp);
    UnixTimeToFileTime(timeValue,&ft);
    BOOL ret = SetFileTime(hFile,NULL,&ft,NULL);
    ret = ret && SetFileTime(hFile, NULL, &ftminus, NULL);
    if (ret == FALSE) {
      std::cout << "could not change last access field." << std::endl;
    }
    CloseHandle(hFile);
  }

}

int main () {
	changeFileTime("<some existing file here>");
   return 0;
}