What is RegQueryValueEx?
In this article. This function retrieves the type and data for a specified value name associated with an open registry key. Copy. LONG RegQueryValueEx( HKEY hKey, LPCWSTR lpValueName, LPDWORD lpReserved, LPDWORD lpType, LPBYTE lpData, LPDWORD lpcbData );
What does RegOpenKey mean?
RegOpenKey opens the specified registry key. If this parameter is NULL or a pointer to an empty string, the function returns the handle to the predefined hKey parameter. phkResult. A pointer to a variable that receives a handle to the opened key.
What is Regsetvalue?
Sets the value, name and type of a specific registry key. Handle to an open registry key. The name of the subkey whose value is to be set.
What is Winreg H?
RegEnumValueA function (winreg.h) – Win32 apps Enumerates the values for the specified open registry key. The function copies one indexed value name and data block for the key each time it is called.
What does Reg_dword 0x1 mean?
LogFileFsCompress REG_DWORD 0x1 Default: 0x1. Compresses the log file if it is on an NTFS partition. The default is to compress the log file.
What is the difference between Reg_sz and Reg_expand_sz?
REG_SZ is the default data type and does not have data type descriptor in the reg file. REG_EXPAND_SZ requires a data type descriptor (2) and is in the form specified.
What is Lptstr C++?
LPTSTR is a pointer to a (non-const) TCHAR string. In practice when talking about these in the past, we’ve left out the “pointer to a” phrase for simplicity, but as mentioned by lightness-races-in-orbit they are all pointers.
What is RegEnumValue?
The winreg. h header defines RegEnumValue as an alias which automatically selects the ANSI or Unicode version of this function based on the definition of the UNICODE preprocessor constant.
What is Reg_dword in registry?
Most hardware component information is stored as binary data, and can be displayed in an editor in hexadecimal format. REG_DWORD – This type represents the data by a four byte number and is commonly used for boolean values, such as “0” is disabled and “1” is enabled.
Is there an alias for regqueryvalueexa in winreg.h?
The winreg.h header defines RegQueryValueEx as an alias which automatically selects the ANSI or Unicode version of this function based on the definition of the UNICODE preprocessor constant. Mixing usage of the encoding-neutral alias with code that not encoding-neutral can lead to mismatches that result in compilation or runtime errors.
How to use regsetkeyvalue in winreg.h?
Consider using the RegSetKeyValue function, which provides a more convenient way to set the value of a registry key. The winreg.h header defines RegSetValueEx as an alias which automatically selects the ANSI or Unicode version of this function based on the definition of the UNICODE preprocessor constant.
What is the return value of regqueryvalueexa function?
If the lpValueName registry value does not exist, RegQueryValueEx returns ERROR_FILE_NOT_FOUND and the value returned through the lpcbData parameter is undefined. If the function succeeds, the return value is ERROR_SUCCESS. If the function fails, the return value is a system error code.
Do you set cbdata to 0 for regsetvalueexa?
For string-based types, such as REG_SZ, the string must be null -terminated. With the REG_MULTI_SZ data type, the string must be terminated with two null characters. Note lpData indicating a null value is valid, however, if this is the case, cbData must be set to ‘0’.