[ros-dev] CommConfigDialog() and serialui.dll

[Thomas Weidenmueller]

Saveliy Tretiakov wrote:

> Maybe this is because you pressed cancel button and 
> ERROR_CALL_NOT_IMPLEMENTED
> was set somewhere else? It returns FALSE when cancel button is pressed.

no, in my copy of win XP calling drvCommConfigDialogA always returns 
ERROR_CALL_NOT_IMPLEMENTED. Calling the unicode version works, it 
returns FALSE/0/ERROR_SUCCESS or ERROR_CANCELLED when correct parameters 
are passed to it.

> From CommConfig dialog description:
> If the function succeeds, the return value is nonzero.
> If the function fails, the return value is zero. To get extended error 
> information, call *GetLastError*.

I'm talking about drvCommConfigDialog, not CommConfig. However 
CommConfig calls drvCommConfigDialog, which appears to return 
ERROR_SUCCESS, ERROR_CANCELLED or another win32 error code, which is not 
a BOOL.

> I think drvCommConfigDialog should return the same.

As i mentioned above, it appears to return a win32 error code, not a 
BOOL in windows XP, which leads to the conclusion that 
drvCommConfigDialog doesn't have the exact same prototype as CommConfig.

> Maybe adding SetLastError(ERROR_CANCELLED) and 
> SetLastError(ERROR_SUCCESS) will solve the problem?

I propose only CommConfig should set the last error, if 
drvCommConfigDialog didn't return ERROR_SUCCESS or ERROR_CANCELLED. Then 
returning TRUE from CommConfig when drvCommConfigDialog returned 
ERROR_SUCCESS and returning FALSE in all other cases should implement it 
correctly. Instead of setting the last error code in 
drvCommConfigDialog, the function should return it directly.

Best Regards,
Thomas