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How to Memory Map Large Files Read-Only in Python

This code demonstrates reading only the tail of a large file using a read-only memory map (mmap) to avoid loading the entire file into memory.

mmap file-io memory-efficient
Python 
import mmap
import os

def read_tail_with_mmap(filepath, bytes_from_end=64):
    """Read the last bytes of a large file using a read-only mmap."""
    file_size = os.path.getsize(filepath)
    start = max(0, file_size - bytes_from_end)

    with open(filepath, "rb") as f:
        with mmap.mmap(f.fileno(), length=0, a…
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