25 lines
799 B
Python
25 lines
799 B
Python
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from __future__ import annotations
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from typing import IO, Callable
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def get_fileno(file_like: IO[str]) -> int | None:
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"""Get fileno() from a file, accounting for poorly implemented file-like objects.
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Args:
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file_like (IO): A file-like object.
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Returns:
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int | None: The result of fileno if available, or None if operation failed.
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"""
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fileno: Callable[[], int] | None = getattr(file_like, "fileno", None)
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if fileno is not None:
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try:
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return fileno()
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except Exception:
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# `fileno` is documented as potentially raising a OSError
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# Alas, from the issues, there are so many poorly implemented file-like objects,
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# that `fileno()` can raise just about anything.
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return None
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return None
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