Read file in chunks - RAM-usage, read Strings from binary files

Question

i\'d like to understand the difference in RAM-usage of this methods when reading a large file in python.

Version 1, found here on stackoverflow:

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Answer 1

I think probably the best and most idiomatic way to do this would be to use the built-in iter() function with a sentinel value to create and use an iterable as shown below. Note that the last chunk might be less that the requested chunk size if the file size isn't an exact multiple of it.

from functools import partial

CHUNK_SIZE = 1024
filename = 'testfile.dat'

with open(filename, 'rb') as file:
    for chunk in iter(partial(file.read, CHUNK_SIZE), b''):
        process_data(chunk)

Update: Don't know when it was added, but almost exactly what's above is in now shown as an example in the official documentation of the iter() function.