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pythonbyte

Declaring a single byte variable in Python

How do we declare a single byte variable in Python? I would like to achieve the following result represented in C:

unsigned char c = 0xFF;

I would like to know if it is possible to declare an 8-bit variable in Python.

Solution

  • Python doesn't differentiate between characters and strings the way C does, nor does it care about int bit widths. For a single byte, you basically have three choices:

    1. A length 1 bytes (or bytearray) object mychar = b'\xff' (or mychar = bytearray(b'\xff'))
    2. An int that you don't assign values outside range(256) (or use masking to trim overflow): mychar = 0xff
    3. A ctypes type, e.g. mychar = ctypes.c_ubyte(0xff)

    The final option is largely for dealing with C functions through ctypes, it's otherwise slow/not Pythonic. Choosing between options 1 and 2 depends on what you're using it for; different use cases call for different approaches (though indexing/iterating the bytes object would get you the int values if you need to use both forms).