lwt_lock_file.mli
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(* Copyright (c) 2018 Dynamic Ledger Solutions, Inc. <contact@tezos.com> *)
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(** Simple abstraction over Unix lockfiles *)
open Error_monad
(** [try_with_lock ?close_on_exec ?unlink_on_exit ~when_locked
~filename f] tries to take a lock on file [filename] and calls [f]
if the lock was successfully taken. If the lock was previously
taken, [when_locked] is called instead and [f] is ignored.
This function may fail with an I/O exception wrapped in the error
monad if something unexpected happened. *)
val try_with_lock :
when_locked:(unit -> 'a tzresult Lwt.t) ->
filename:string ->
(unit -> 'a tzresult Lwt.t) ->
'a tzresult Lwt.t