Module elock

func elock

elock creates a file-system level lockfile associated with a given filename. This is an advisory lock only and requires all callers to use elock and eunlock in order to protect the file.

On Linux, this uses flock(1) for efficient kernel-level locking. On Darwin/macOS, this uses mkdir-based spinlocking as a cross-platform fallback.

These locks are exclusive. These locks are NOT recursive - if you already own the lock and try to acquire it again, it will return an error immediately to avoid hanging.

If the file doesn’t exist, it is created.

func elock_get_fd

elock_get_fd gets the file descriptor (if any) that our process has associated with a given on-disk lockfile. On Darwin, returns “1” (a placeholder) since mkdir-based locking doesn’t use file descriptors. Returns 1 (failure) if the file is not locked by this process.

func elock_locked

elock_locked checks if a file is currently locked (by any process, not just this one).

func elock_unlocked

elock_unlocked checks if a file is not currently locked.

func eunlock

eunlock unlocks a previously locked file and releases the associated resources (file descriptor on Linux, lock directory on Darwin). Returns an error if the file is not currently locked by this process.