ClearCommError calls NtDeviceIoControlFile and, from IOCTL_SERIAL_GET_COMMSTATUS, it returns a SERIAL_STATUS structure
IOCTL_SERIAL_GET_COMMSTATUS data format
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Phan Anh Dung (GAM.VN.DAP)
21
Reputation points
In the function ClearCommError from Winbase API, an IOCTL call with code IOCTL_SERIAL_GET_COMMSTATUS is sent to the device (the COM port) driver and a pointer Request is passed as a parameter. What exactly is expected to be returned to the function by this pointer from the driver side? What is the format of the thing the pointer points to after the call? If it is a struct then what struct?
Windows development | Windows API - Win32
Windows for business | Windows Client for IT Pros | User experience | Other
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Reza-Ameri 45,681 Reputation points Volunteer Moderator2021-07-09T14:52:25.143+00:00 Are you using the Windows 11?
What programming language are you using? e.g. C++ , C# ,... -
Phan Anh Dung (GAM.VN.DAP) 21 Reputation points
2021-07-09T15:12:53.217+00:00 Yes, I'm using Windows 11.
The application is written in C, using Winbase API, the particular function is ClearCommError (see https://learn.microsoft.com/en-us/windows/win32/api/winbase/nf-winbase-clearcommerror). The driver is a standard COM port driver using KMDF.
Any help would be greatly appreciated, thanks!
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Answer accepted by question author
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Castorix31 91,511 Reputation points2021-07-10T18:20:00.933+00:00 -
Phan Anh Dung (GAM.VN.DAP) 21 Reputation points
2021-07-11T05:18:44.17+00:00 This is exactly what I was looking for, thank you!
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