Python 3.5+pathlibfunction

.write_bytes()

reading/writing

Write bytes to the file, overwriting it entirely, and return the number of bytes written — the binary counterpart of `.write_text()`.

Syntax

p.write_bytes(data)

An existing file is truncated without any warning, and there is no append mode here — to add to the end use open(p, 'ab'). Missing parent directories are not created either: without them you get FileNotFoundError, so call p.parent.mkdir(parents=True, exist_ok=True) first.

Examples

from pathlib import Path
p = Path('test_pathlib.bin')
p.write_bytes(b'\xff\xfe') # → 2
p.read_bytes() # → b'\xff\xfe'

See also

Common errors

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