IsGUIThread function (winuser.h)
Determines whether the calling thread is already a GUI thread. It can also optionally convert the thread to a GUI thread.
Syntax
BOOL IsGUIThread(
[in] BOOL bConvert
);
Parameters
[in] bConvert
Type: BOOL
If TRUE and the thread is not a GUI thread, convert the thread to a GUI thread.
Return value
Type: BOOL
The function returns a nonzero value in the following situations:
- If the calling thread is already a GUI thread.
- If bConvert is TRUE and the function successfully converts the thread to a GUI thread.
If bConvert is TRUE and the function cannot successfully convert the thread to a GUI thread, IsGUIThread returns ERROR_NOT_ENOUGH_MEMORY.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows XP [desktop apps only] |
| Minimum supported server | Windows Server 2003 [desktop apps only] |
| Target Platform | Windows |
| Header | winuser.h (include Windows.h) |
| Library | User32.lib |
| DLL | User32.dll |