From: Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com>
Date: Wed, 29 May 2019 18:24:32 +0000 (-0700)
Subject: bpo-36794: Document that Lock.acquire is fair. (GH-13082)
X-Git-Tag: v3.7.4rc1~84
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=4e1e887203ef069bf293ecabd945f7567d6a4879;p=thirdparty%2FPython%2Fcpython.git

bpo-36794: Document that Lock.acquire is fair. (GH-13082)


https://bugs.python.org/issue36794
(cherry picked from commit 34f4f5efea730504216ee19f237734e0bb0104ee)

Co-authored-by: Hrvoje Nikšić <hniksic@gmail.com>
---

diff --git a/Doc/library/asyncio-sync.rst b/Doc/library/asyncio-sync.rst
index 291310d71414..993bd13fb030 100644
--- a/Doc/library/asyncio-sync.rst
+++ b/Doc/library/asyncio-sync.rst
@@ -66,6 +66,13 @@ Lock
       This method waits until the lock is *unlocked*, sets it to
       *locked* and returns ``True``.
 
+      When more than one coroutine is blocked in :meth:`acquire`
+      waiting for the lock to be unlocked, only one coroutine
+      eventually proceeds.
+
+      Acquiring a lock is *fair*: the coroutine that proceeds will be
+      the first coroutine that started waiting on the lock.
+
    .. method:: release()
 
       Release the lock.