CheckPointer macro
[The feature associated with this page, DirectShow, is a legacy feature. It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation. Those features have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use MediaPlayer, IMFMediaEngine and Audio/Video Capture in Media Foundation instead of DirectShow, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]
Checks whether a pointer is NULL. If the pointer is NULL, the function or method in which the macro appears returns the specified value.
Syntax
HRESULT CheckPointer(
p,
ret
);
Parameters
-
p
-
Pointer to check.
-
ret
-
Value that the function or method returns if p is NULL.
Return value
The surrounding function returns ret if p is NULL. Otherwise, the macro does not cause the surrounding function to return.
Examples
HRESULT MyFunction(VOID *pSomeParameter)
{
// Return E_INVALIDARG if pSomeParameter is NULL.
CheckPointer(pSomeParameter, E_INVALIDARG)
// Rest of the function (not shown).
}
Requirements
| Requirement | Value |
|---|---|
| Header |
|