On Wed, 21 Jan 2015 18:44:41 +0100 "Michael Kerrisk (man-pages)" <mtk.manpages@xxxxxxxxx> wrote: > Hi Jeff, > > I was recently checking some details of the man page for OFD locks, > and realized that one paragraph is somewhat misleading: > > Open file description locks always conflict with traditional > record locks, even when they are acquired by the same process on > the same file descriptor. > > This doesn't capture the full story, as far as I can tell. In > particular if we have two processes that take locks on the same region > of a file as follows: > > F_OFD_SETLK F_RDLCK > and > F_SETLK F_RDLCK > > then those pair of locks are compatible. I assume that's expected > behavior, right? I've drafted the patch below for the man page. Seem > okay? > > Cheers, > > Michael > > diff --git a/man2/fcntl.2 b/man2/fcntl.2 > index 59f22ce..03c2ae8 100644 > --- a/man2/fcntl.2 > +++ b/man2/fcntl.2 > @@ -495,7 +495,10 @@ and are only automatically released on the last close > of the open file description, > instead of being released on any close of the file. > .PP > -Open file description locks always conflict with traditional record locks, > +Conflicting lock combinations > +(i.e., a read lock and a write lock or two write locks) > +where one lock is an open file description lock and the other > +is a traditional record lock conflict > even when they are acquired by the same process on the same file descriptor. > > Open file description locks placed via the same open file description > > Yes, that is expected behavior and your patch looks good to me. Acked-by: Jeff Layton <jlayton@xxxxxxxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
