OutputDebugStringA function (debugapi.h)
Sends a string to the debugger for display.
Syntax
void OutputDebugStringA(
[in, optional] LPCSTR lpOutputString
);
Parameters
[in, optional] lpOutputString
The null-terminated string to be displayed.
Return value
None
Remarks
If the application has no debugger, the system debugger displays the string if the filter mask allows it. (Note that this function calls the DbgPrint function to display the string. For details on how the filter mask controls what the system debugger displays, see the DbgPrint function in the Windows Driver Kit (WDK) on MSDN.) If the application has no debugger and the system debugger is not active, OutputDebugString does nothing.Prior to Windows Vista: The system debugger does not filter content.
OutputDebugStringW converts the specified string based on the current system locale information and passes it to OutputDebugStringA to be displayed. As a result, some Unicode characters may not be displayed correctly.
Applications should send very minimal debug output and provide a way for the user to enable or disable its use. To provide more detailed tracing, see Event Tracing.
Visual Studio has changed how it handles the display of these strings throughout its revision history. Refer to the Visual Studio documentation for details of how your version deals with this.
Note
The debugapi.h header defines OutputDebugString 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. For more information, see Conventions for Function Prototypes.
Requirements
Minimum supported client | Windows XP [desktop apps | UWP apps] |
Minimum supported server | Windows Server 2003 [desktop apps | UWP apps] |
Target Platform | Windows |
Header | debugapi.h (include Windows.h) |
Library | Kernel32.lib |
DLL | Kernel32.dll |