I am assuming that in the SDL2 internals, it should have some structure that keeps track of all the existing windows in a program. Is it possible to get the existing windows (or at least a count of the existing, open ones) in SDL2?
Related
I have a 32-bit windows old application (with the C/Win32 source) that creates its data file in the same folder where the executable is.
Because the application has no installation program and the user can place the executable wherever he/she wants, the application has a dialog to inform the user where its data is located.
But under Microsoft Vista/Seven if the user puts the application in the Program Files or any other system-protected folder the data file gets virtualized and moved to a virtual-store.
If, under Vista/Seven, I still want to inform the user where the data file is located:
(without preventing virtualization in the manifest file)
How can I know (programatically) if the data file is virtualized? Or if the folder where the executable is located implies that data file will be virtualized?
Assuming I know the data file is virtualized, how can I know (programatically) the location of the virtual folder, to show it in the information dialog?
I have found the following question very close to what I'm asking but it doesn't show the solution (if any) of knowing when virtualization is taking place for a file, and where it gets virtualized.
How to detect file redirection to the Windows VirtualStore?
Virtualization is transparent to the app. The only way to know whether it is being virtualized is to ask the OS, per the answer in the question you linked to (use GetTokenInformation() with the TokenVirtualizationEnabled flag), but there is no way (that I know of) of asking the OS where the virtualized items are actually stored, as it may be different from one OS version to the next. You will have to do some research and then hard-code the paths for each given OS that your app detects at runtime.
If you are going to update your code to detect virtualization, then you are better off updating the code to play nicer with UAC instead. Stop storing your files where they do not belong, and start storing them where Microsoft wants you to store them. In this case, within the user's profile instead. Use SHGetFolderPath() or related function to locate the user's CSIDL_LOCAL_APPDATA folder (or SHGetKnownFolderPath() on Vista+ to locate the FOLDERID_LocalAppData folder), then create a subfolder underneath it for your app to store its data files in.
I am in the middle of writing a tool that finds lost files of an iTunes library, for both Mac and Windows. On the Mac, I can quickly find files by naming using the wonderful "CatalogSearch" function.
On Windows, however, there seems to be no OS API for searching by file name (or is there?).
After some googling, I learned that there are tools (like TFind, Everything) that read the NTFS directory directly and scan it to find files by name.
I would like to do the same, but without having to start from scratch (although I've written quite a few disk tools in the past, I've never had the energy to dig into NTFS).
I wonder if there are ready-made libs around, possibly as a .dll, that would give me this search feature: Pass in a file name, get back its path.
Alternatively, what about the Windows indexing service? At least when I tried this on a recently installed XP Home system, the Search operation under the Start menu would actually scan all directories, which suggests that it has no complete database. As I'm not a Windows user at all, I wonder why this isn't working.
In the end, the complete solution I need is: I have a list of file names to find, and I need code that searches the entire disk (or uses a DB for it) to get me all results in one go. E.g, the search should not start a new full scan for every file I'm looking up. That's why I think the MFT way would be optimal, as it could quickly iterate over all names, comparing each to my list.
The best way to solve your problem seems to be by using the Windows Change Journal.
Problem: If it is not enabled for a volume or the volume is a non-NTFS you need a fallback (or enable the Change Journal if it is NTFS). You need administrator rights as well to access the Change Journal.
You get the files by using the FSCTL_ENUM_USN_DATA and DeviceIOControll with LowUsn=0. This directly accesses the MFT and writes all filenames into the supplied buffer. Because it sequentially acesses the MFT it is faster than the FindFirstFile API.
I am in the middle of writing a tool that finds lost files of an iTunes library, for both Mac and Windows. On the Mac, I can quickly find files by naming using the wonderful "CatalogSearch" function.
On Windows, however, there seems to be no OS API for searching by file name (or is there?).
After some googling, I learned that there are tools (like TFind, Everything) that read the NTFS directory directly and scan it to find files by name.
I would like to do the same, but without having to start from scratch (although I've written quite a few disk tools in the past, I've never had the energy to dig into NTFS).
I wonder if there are ready-made libs around, possibly as a .dll, that would give me this search feature: Pass in a file name, get back its path.
Alternatively, what about the Windows indexing service? At least when I tried this on a recently installed XP Home system, the Search operation under the Start menu would actually scan all directories, which suggests that it has no complete database. As I'm not a Windows user at all, I wonder why this isn't working.
In the end, the complete solution I need is: I have a list of file names to find, and I need code that searches the entire disk (or uses a DB for it) to get me all results in one go. E.g, the search should not start a new full scan for every file I'm looking up. That's why I think the MFT way would be optimal, as it could quickly iterate over all names, comparing each to my list.
The best way to solve your problem seems to be by using the Windows Change Journal.
Problem: If it is not enabled for a volume or the volume is a non-NTFS you need a fallback (or enable the Change Journal if it is NTFS). You need administrator rights as well to access the Change Journal.
You get the files by using the FSCTL_ENUM_USN_DATA and DeviceIOControll with LowUsn=0. This directly accesses the MFT and writes all filenames into the supplied buffer. Because it sequentially acesses the MFT it is faster than the FindFirstFile API.
Windows lets you develop a filter driver to catch file I/O's on VFS. But I can't seem to find something similar for Mac. It does have something called Filter Schemes, but those are for HFS+. Anyone know if there is a way for me to intercept file I/O's on Mac without using programs like MacFUSE?
I found out that Mac OS X does not allow filter drivers at all.
“A stacking file system (sometimes called a filter file system) sits on top of another file system and modifies its behavior in some way. The canonical example of a stacking file system is an encryption file system. You could stack this file system on top of any existing file system to provide encryption support. Apple does not support the development of stacking VFS plug-ins on Mac OS X” (http://developer.apple.com/mac/library/qa/qa2001/qa1242.html)
kauth (introduced in OS X 10.4) is the closest thing to FS filter drivers.
Here is a nice write-up on the various APIs present on Mac OS X. It should be a good starting point.
Link
I'm not at all familier with the Windows technologies that you mention, but it sounds like you might be looking for FSEvents.
http://developer.apple.com/mac/library/documentation/Darwin/Conceptual/FSEvents_ProgGuide/Introduction/Introduction.html
The file system events API provides a
way for your application to ask for
notification when the contents of a
directory hierarchy are modified. For
example, your application can use this
to quickly detect when the user
modifies a file within a project
bundle using another application.
It also provides a lightweight way to
determine whether the contents of a
directory hierarchy have changed since
your application last examined them.
For example, a backup application can
use this to determine what files have
changed since a given time stamp or a
given event ID.
You should read this document if your
application works with a large number
of files—particularly if your
application works with large
hierarchies of files.
I have been trying to find a way to "defragment" the registry on my Windows machine. Firstly, does this make sense? Any benefits in doing this? (Not much love on superuser.com) Secondly, I am looking for a way to rewrite the registry using C/C++ with Windows API. Is there a way to read the registry and write it to a new file getting rid of unused bytes along the way? (I might have to write the new file and then boot into another OS/disk before I can overwrite the original... but I am willing to take that risk.)
Microsoft's PageDefrag does exactly this, as it states on its page "PageDefrag uses the standard file defragmentation APIs to defragment the files."
(A copy of the linked article is here because in typical MSDN style their link is dead.)
http://www.larshederer.homepage.t-online.de/erunt/ - NTREGOPT NT Registry Optimizer
Similar to Windows 9x/Me, the registry files in an NT-based system
can become fragmented over time, occupying more space on your hard
disk than necessary and decreasing overall performance. You should
use the NTREGOPT utility regularly, but especially after installing
or uninstalling a program, to minimize the size of the registry files
and optimize registry access.
The program works by recreating each registry hive "from scratch",
thus removing any slack space that may be left from previously
modified or deleted keys.
http://reboot.pro/index.php?showtopic=11212 - Offreg.dll MS WDK Offline Registry Library
The offline registry library (Offreg.dll) is used to modify a registry hive outside the active system registry. This library is intended for registry update scenarios such as servicing an operating system image. The library supports registry hive formats starting with Windows XP.
Developer Audience
http://reboot.pro/topic/11312-offline-registry/ - Offline Registry MS WDK Command-Line Tool
A command line tool that will allow one to read and write to an offline registry hive.
Reading the values should be possible.
But I've never seen any spec for how the registry files are written to disk, and unless you could find one you'd have to reverse engineer those files in your OS (might be differences between XP and 7 etc). Then you have to remember that the registry isn't just one file, it's multiple files and some of them belongs to certain users and I think they use SIDs rather than user names so even if you move them to a new computer, you have to be sure it's the same OS version with the same users with the same SIDs set up on it.
All this for little or no gain so I'd agree with the superuser users that it wouldn't make sense.