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71 lines
2.7 KiB
Markdown
71 lines
2.7 KiB
Markdown
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[](https://github.com/marketplace/actions/arduino_ci)
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[](https://github.com/RobTillaart/DEVNULL/actions/workflows/arduino-lint.yml)
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[](https://github.com/RobTillaart/DEVNULL/actions/workflows/jsoncheck.yml)
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[](https://github.com/RobTillaart/DEVNULL/blob/master/LICENSE)
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[](https://github.com/RobTillaart/DEVNULL/releases)
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# DEVNULL
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Arduino library for a /dev/null stream
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## Description
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The library implements a stream class that mimics the **/dev/null**
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device of a Linux system. You can write everything to it, you can
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never read data from it as it always returns EOF (end of file);
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The 0.1.0 version is a minimal implementation that can be optimized.
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it implements the **write(const uint8_t data)** call and e.g. a float is still
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converted to individual characters that are send one after another.
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Strings and text send every byte.
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The advantage is that printing takes time and e.g. one can use it to measure
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the **print** class performance.
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Performance can be increased by implementing all methods of the print interface
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with only a return 0; (or at least **print(Type)** as the **println(T)** would only
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call once extra for the "\n".
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#### Version 0.1.2
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- sets the timeout for reading to 0. No need to wait longer with DEVNULl.
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this improves the **find(...)** calls substantially.
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- added **size_t write( const uint8_t \*buffer, size_t size)** for faster string processing.
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## Interface
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- **DEVNULL()** constructor, sets the timeout to zero.
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- **int available()** always return zero.
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- **int peek()** always returns EOF.
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- **int read()** always return EOF.
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- **void flush()** does nothing but keeps some compilers happy.
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- **size_t write(const uint8_t data)** implements print interface. returns 1.
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0.1.2 added to improve performance a few percent (UNO).
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- **size_t write( const uint8_t \*buffer, size_t size)** implements print interface. returns size.
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## Operation
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Use with care.
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See examples.
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## Future
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- add optional delay to mimic pause / tune behaviour for simulating other devices
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microseconds - milliseconds?
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delay per byte or per call to write? (esp long arrays might need other performance
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feels out of scope for /dev/null
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- add byte counter (uint32_t)
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- add lastWrittenByte() - look at the last byte written to the bottomless pit.
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