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title: "Using QL C, Part One: Opening Devices"
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excerpt: "Tutorial with code examples showing how to open serial port, console, and screen devices in Metacomco QL C, and explaining the difference between buffered and unbuffered I/O using setnbf(). A sample program demonstrates printing output to the QL serial port."
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# Using QL C, Part One: Opening Devices

Tutorial with code examples showing how to open serial port, console, and screen devices in Metacomco QL C, and explaining the difference between buffered and unbuffered I/O using setnbf(). A sample program demonstrates printing output to the QL serial port.