ytdl-org/youtube-dl · error · OSError

Unlocking file failed: %r

Error message

Unlocking file failed: %r

What it means

Error "Unlocking file failed: %r" thrown in ytdl-org/youtube-dl.

Source

Thrown at youtube_dl/utils.py:3531

    whole_high = 0x7fffffff

    def _lock_file(f, exclusive):
        overlapped = OVERLAPPED()
        overlapped.Offset = 0
        overlapped.OffsetHigh = 0
        overlapped.hEvent = 0
        f._lock_file_overlapped_p = ctypes.pointer(overlapped)
        handle = msvcrt.get_osfhandle(f.fileno())
        if not LockFileEx(handle, 0x2 if exclusive else 0x0, 0,
                          whole_low, whole_high, f._lock_file_overlapped_p):
            raise OSError('Locking file failed: %r' % ctypes.FormatError())

    def _unlock_file(f):
        assert f._lock_file_overlapped_p
        handle = msvcrt.get_osfhandle(f.fileno())
        if not UnlockFileEx(handle, 0,
                            whole_low, whole_high, f._lock_file_overlapped_p):
            raise OSError('Unlocking file failed: %r' % ctypes.FormatError())

else:
    # Some platforms, such as Jython, is missing fcntl
    try:
        import fcntl

        def _lock_file(f, exclusive):
            fcntl.flock(f, fcntl.LOCK_EX if exclusive else fcntl.LOCK_SH)

        def _unlock_file(f):
            fcntl.flock(f, fcntl.LOCK_UN)
    except ImportError:
        UNSUPPORTED_MSG = 'file locking is not supported on this platform'

        def _lock_file(f, exclusive):
            raise IOError(UNSUPPORTED_MSG)

        def _unlock_file(f):

View on GitHub (pinned to 956b8c5855)

Solutions

1. Check filesystem state and permissions; the lock could not be released.

When it happens

Trigger: Thrown at youtube_dl/utils.py:3531 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of ytdl-org/youtube-dl@956b8c5855 (2026-08-14). Data as JSON: /api/errors/df4d96785c302b88. Report an issue: GitHub.