Using Macros for Error Handling
COM defines a number of macros that make it easier to work with HRESULT values.
The error handling macros are described in the following table.
| Macro | Description |
|---|---|
| MAKE_HRESULT |
Returns an HRESULT given the severity bit, facility code, and error code that comprise the HRESULT. Note: Calling MAKE_HRESULT for S_OK verification carries a performance penalty. You should not routinely use MAKE_HRESULT for successful results. |
| MAKE_SCODE |
Returns an SCODE given the severity bit, facility code, and error code that comprise the SCODE. |
| HRESULT_CODE |
Extracts the error code portion of the HRESULT. |
| HRESULT_FACILITY |
Extracts the facility code of the HRESULT. |
| HRESULT_SEVERITY |
Extracts the severity bit of the HRESULT. |
| SCODE_CODE |
Extracts the error code portion of the SCODE. |
| SCODE_FACILITY |
Extracts the facility code of the SCODE. |
| SCODE_SEVERITY |
Extracts the severity field of the SCODE. |
| SUCCEEDED |
Tests the severity bit of the SCODE or HRESULT; returns TRUE if the severity is zero and FALSE if it is one. |
| FAILED |
Tests the severity bit of the SCODE or HRESULT; returns TRUE if the severity is one and FALSE if it is zero. |
| IS_ERROR |
Provides a generic test for errors on any status value. |
| HRESULT_FROM_WIN32 |
Maps a system error code to an HRESULT value. |
| HRESULT_FROM_NT |
Maps an NT status value to an HRESULT value. |