What is SetValue in the winreg Python module?

winreg, or Windows registry access, provides functions that expose the Windows registry API to Python. Windows registry is a collection of databases that stores the information and settings of software programs, hardware devices, user preferences, and operating-system configurations.

Registry handle objects

winreg uses a handle object as the registry handle to ensure that the handles are closed correctly, even in cases where the programmer might forget to close them.

The handle object wraps a windows HKEY object and automatically closes it when the object is destroyed. It also supports comparison semantics, so two handle objects will compare true if both of them point to the same Windows underlying handle value.

SetValue method

SetValue associates a value with the specified key.

Syntax

winreg.SetValue(key, sub_key, type, value) 

Parameters

  • key is an already opened key or one of the predefined HKEY_* constants. HKEY constants correspond to various registry entries such as environment variable settings, the physical state of the computer, user preferences, network connections, etc. We must open this key with KEY_SET_VALUE access.

  • subkey is the subkey in the form of a string with which the value is associated.

  • type is an integer that is used to identify the data type. The type is set to string by default, but we can use the SetValueEx method to define other types.

  • value is a string that provides the new value associated with the key.

  • Values greater than 2048 bytes are suggested to be stored in files with the filenames stored in the configuration registry.
  • If the subkey is not provided, the function creates it automatically.

Return value

This method raises an auditing event winreg.SetValue with the parameters key, subkey, type, and value. An audit event is raised when an OS system-level change is made to be reported to the system audit logger that runs as part of the kernel.

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