Request body: block write events while reading body. If write events are not blocked, an extra write event might happen for various reasons (e.g. as a result of a http pipelining), resulting in incorrect body being passed to a post handler. The problem manifested itself with the dav module only, as this is the only module which reads the body from a content phase handler (in contrast to exclusive content handlers like proxy). Additionally, dav module used to dump core in such situations due to ticket #238. See reports here: http://mailman.nginx.org/pipermail/nginx-devel/2012-November/002981.html http://serverfault.com/questions/449195/nginx-webdav-server-with-auth-request