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

yield is the keyword in python used for generator expressions. That means that the next time the function is called (or iterated on), the execution will start back up at the exact point it left off last time you called it. The two functions behave identically; the only difference is that the first one uses a tiny bit more call stack space than the second. However, the first one is far more reusable, so from a program design standpoint, the first one is actually better.

EDIT: Also, one other difference is that the first one will stop reading once all the data has been read, the way it should, but the second one will only stop once either f.read() or process_data() throws an exception. In order to have the second one work properly, you need to modify it like so:

f = open(file, 'rb')
while True:
    piece = f.read(1024)  
    if not piece:
        break
    process_data(piece)
f.close()