The registry includes the following five main items:
1.HKDY_CLASSES_ROOT: contains all the information needed to start the application, including the extension, the relationship between the application and the document, the driver name, the DDE and OLE information, the class ID number, the icons of the application and the document, etc.
2.HKEY Current User: Contains the configuration information of the currently logged-in user, including environment variables, personal programs, desktop settings, etc.
3.HKEY_LOCAL_MACHINE: It contains the system information of the local computer, including hardware and operating system information, such as device drivers, security data and various software setting information special for the computer.
4.HKEY _ User: Contains the configuration data used by all users of the computer, which can only be accessed when users log in to the system. This information tells the system the icon used by the current user, the activated program group, the content of the start menu, the color and font, etc.
5.HKEY current configuration: Store the current hardware configuration information and map it from HKEY local machine.
Please refer to the following introduction for specific instructions:
1.HKEY _ Category _ Root Keyword
The root key of HKEY _ class _ root records the information content of all data files in Windows operating system, mainly recording the file name suffixes of different files and their corresponding applications. When a user double-clicks a document, the system can start the corresponding application through this information.
HKEY _ Class _ Root Key consists of several subitems, which are divided into two types: one is the extension of registered files, and the other is the information about various file types. Because this root key contains the largest number of sub-items, let's briefly introduce the meaning of the sub-items below it with the Avifile sub-item:
1.CLSID subkey
The first subitem under the Avifile subitem is CLSID, that is, Classification ID. When you select it, you can see its default key value. Windows systems can use this class identification number to identify files of the same type. There is also a subitem "CLSID" under HKEY _ Class _ root primary key, which contains the class identification of all registered files.
2.Compressors subitem
The two subkeys auds and vids below this branch respectively give the class identification of audio and video data compression programs, and the corresponding processing programs can be found through these class identification.
(1) auds subitem
This subitem is located in the branch of HKEY _ class _ root \ avifile \ compressors \ auds, and is used to set the class identifier of the audio data compressor.
(2) vids subitem
This subitem is located on the branch of HKEY _ class _ root \ avifile \ compressors \ vids, and is used to set the class identifier of the video data compressor.
3.DefaultIcon subitem
This subitem is used to set the default icon of avifile.
4.RIFFHandlers subitem
This subitem is used to set the handle of the RIFF file. Under this subitem, the class identifiers of AVI and WAVE files are included.
(1) AVI subkey
This subitem is located in HKEY _ Class _ Root \ Avifile \ Riffhandlers \ AVI branch, and is used to set the class identification of AVI file.
(2) WAVE subkey
This subitem is located in HKEY _ class _ root \ avifile \ riffhandlers \ WAVE branch, and is used to set the class identifier of the WAVE file.
5. Agreement sub-item
The subitems under this branch contain the paths and file names of the executing program and the editing program.
(1) StdExecute subitem
This subitem has the following subitem structure:
HKEY _ Class _ Root \ avifile \ Protocol \ stdexecute \ Server, which is used to specify the standard execution program of avifile.
(2) StdFileEditing subitem
This subitem is located on the branch of HKEY _ class _ root \ avifile \ protocol \ STD file editing, and is used to set up a standard file editing program.
There are three subitems under this subitem:
① server subitem
This subitem is located in the branch of HKEY _ class _ root \ avifile \ protocol \ STD file editing \ server, and is used to specify the editing program.
②PackageObjects subitem
The subitem is located in HKEY _ class _ root \ avifile \ protocol \ STD file editing \
On the PackageObjects branch, it is used to specify the package object editor that opens avifile.
③ Verb subitem
This sub-item is located in the branch of HKEY _ class _ root \ Avifile \ Protocol \ STD file editing \ verb, and is used to set the working state when opening the standard avi file editing program.
In addition, there are two subkeys "Handler" and "Handlers".
6. Shell subkey
This subitem is located on the branch of HKEY _ class _ root \ avifile \ shell and is used to set the shell of the video file.
(1) Open the subkey
This subitem has the following subitem structure:
HKEY _ class _ ROOT \ avifile \ Shell \ Open \ Command
It is used to set the program to "open" the avi file.
(2) playing the subkey
This subitem has the following subitem structure:
HKEY _ class _ root \ avifile \ shell \ play \ command, which specifies the program used for the Play command.
7.shellex subkey
This subitem is located on the branch of HKEY _ Class _ Root \ Avifile \ Shellex. The subitem of this branch contains the shell extension of the video file, and there is a subitem of PropertySheetHandlers under this subitem, which is used to set the file handle of "Avi page". There is also an AviPage subitem under the PropertySheetHandlers subitem, which is used to set the class identification of AviPage.
Second, HKEY _ current _ user root key
The information stored in the root key of HKEY _ current _ user (sub-key information of current user) is the same as that stored in HKEY _ user. Default branch. Any modification of the information in the root key of HKEY _ current _ user will result in modification of the subkey information of HKEY _ user.
Third, the key _ local _ machine
The root key store of HKEY_LOCAL_MACHINE is used to control the settings of the system and software. Because these settings are set for users who use Windows systems and belong to public configuration information, they have little to do with specific users. There are five subitems under this root item:
1. Hardware subkey
This subitem contains information about the floating-point processor and serial port used by the system. Some information about hypertext terminal, digital coprocessor and serial port is stored below. The hardware subitem includes three subitems:
Description: used to store system information;
DEVICEMAP: used to store device images;
RESOURCEMAP
2.SAM subitem
This subitem is protected by the system, so its contents cannot be viewed.
3. Secure subkey
This subitem is located on the branch of HKEY_LOCAL_MACHINE\Security, which is reserved only for advanced functions in the future.
4. Software subkey
This subkey contains information about all installed 32-bit applications. The control information of each program is installed in the corresponding sub-items. Because the applications installed by different machines are different from each other, the sub-item information under this sub-item will be very different.
5. System subitem
This subitem stores the information used at startup and the information needed when repairing the system, including the description information and configuration information of each driver. There is a CurrentControlSet subitem under the System subitem, and the system saves all the information of the current driver control set under this subitem.
Four, HKEY _ user root key
The HKEY user root key stores the information of the default user. Default), currently logged-in user and software. There are three subkeys under it:. Default sub-item, S- 1-5-21229272821-436374067-1060284298-1000 and s.
Configuration of. The default subitem is used for new users created in the future. New users generate their own configuration files according to the configuration information of default users, including environment, screen, sound and other information.
There are nine subkeys under. By default. Introduce some of them:
1.AppEvents subitem
It contains a list of various application events (including event names, descriptions and sounds of various system functions). Below it are two subkeys, EventLabels (alphabetical list) and Schemes (list classified by event).
2. Control panel subitems
Its contents are related to the settings such as desktop, cursor, keyboard and mouse. Changing their key values will change the corresponding working environment or parameters.
3. Keyboard layout subitems
This subitem is located on the branch of the HKEY user. Default \ Keyboard Layout, which is used to set the layout of the keyboard, such as the loading order of keyboard languages. The following three subitems are provided under this subitem:
Pre-loaded subitem
(1) This subitem is located on the HKEY user. Default \ Keyboard Layout \ preload branch, which is used to set the loading order of keyboard languages. The number of subitems under the Preload subitem is related to the keyboard language installed in the system.
(2) Substituents
This subitem is located in the branch of HKEY user. Default \ KeyboardLayout \ Replaces, which is used to set the alternative keyboard language layout. Under normal circumstances, the setting of this subitem is empty.
(3) Switch subitems
This subitem is located on the branch of the HKEY user. The default is \ KeyboardLayout \ Toggle, which is used to select the keyboard language.
V. HKEY _ Current _ Configure Root Key
If two or more sets of hardware profiles are set in Windows, the user will be asked to choose which set of profiles to use when the system starts. The root key of HKEY's current configuration stores the information of the current configuration file.