Serial Port Programming Part 10 - Reading/Writing Status of Control Lines: DTR/RTS/CTS/DSR

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If the user is interested in finding out the status of Control Lines:DTR/DSR/RTS/CTS. He can use 'TIOCMGET' control code in the ioctl call.

'TIOCMSET' control code in  ioctl allows you to set/clear DTR and RTS lines as they are output.

Example Code:


Output:

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