Perl Guru Forums: Perl Programming Help: Win32 Programming Help: Win32::API::Prototype and FILETIME

CGI/Perl Guide | Learning Center | Forums | Advertise | Login

Site Search: in


	MAIN INDEX	SEARCH POSTS	WHO'S ONLINE	LOG IN

Home: Perl Programming Help: Win32 Programming Help:
Win32::API::Prototype and FILETIME

jbenezech
Novice

Apr 21, 2007, 3:31 AM

Post #1 of 2 (3650 views)

Win32::API::Prototype and FILETIME	Can't Post

Hi All,

I am trying to use the Win32::API::Prototype module to write some files to the Internet cache. I can create the cache entry ok by calling CreateUrlCacheEntry and CommitUrlCacheEntry. But now I'd like to specify the expire date of this cache entry and that's where trouble start: I understand Win32 FILETIME structure is like this:

typedef struct _FILETIME {
DWORD dwLowDateTime;
DWORD dwHighDateTime;
}

First of all, does anybody knows what these LowDateTime and HighDateTime actually mean ?

Then how do I convert the SYSTEMTIME to a FILETIME ?

- First I need to create the SYSTEMTIME structure. I did:

Code

 my $pSystemTime = pack("S8",$wYear,$wMonth,$wDayofWeek,$wDay,$wHour,$wMin, $wSec,$wMilli);

- Then I need to convert it to a FILETIME. Like this:

Code

  
 
      SystemTimeToFileTime($pSystemTime,$pFileTime);

At that point, the perl interpreter crashes. So I guess I must be doing something wrong, either because the pack() uses a wrong template or because I use the SystemTimeToFileTime function incorrectly...

- Then I would need to extract the LowDateTime and HighDateTime from that resulting structure but I have no clue how to do this.

As always any help would be greatly appreciated.

Cheers,

Jerome

jbenezech
Novice

Apr 21, 2007, 11:13 PM

Post #2 of 2 (3644 views)

Re: [jbenezech] Win32::API::Prototype and FILETIME [In reply to]	Can't Post

Finally got this thing working. Problem was that I did not initialize the FILETIME structure. Here is the working code for future reference:

Code

 sub getFileTime { 
 # Create a SYSTEMTIME object 
 my $wYear = '2099'; 
 my $wMonth = '12'; 
 my $wDayofWeek = '6'; 
 my $wDay = '1'; 
 my $wHour = '10'; 
 my $wMin = '12'; 
 my $wSec = '30'; 
 my $wMilli = '0'; # Now, pack the object. The SYSTEMTIME object is basically 8 WORDs  
 # packed into a structure.  
 my $pSystemTime = pack("S8",$wYear,$wMonth,$wDayofWeek,$wDay,$wHour,$wMin, $wSec,$wMilli);  # Convert the SYSTEMTIME to a FILETIME object 
 my $pFileTime = ' ' x 2 x 8; 
 if (SystemTimeToFileTime($pSystemTime,$pFileTime)) { 
  my ($low, $high) = unpack("L2", $pFileTime); 
  print "Got file time low $low\n"; 
  print "Got file time high $high\n"; 
  return ($low, $high); 
 } else { 
  print "Could not convert time: $!\n"; 
  return (0,0); 
 }}

Search for (options)

Web Applications & Managed Hosting Powered by Gossamer Threads
Visit our Mailing List Archives