ENOBUFS missing in man recv(2) [Initially: What does nflog_unbind_pf actually do?]

[Helmut Grohne <h.grohne@cygnusnetworks.de>]

On Fri, Feb 11, 2011 at 03:29:36PM +0100, Pablo Neira Ayuso wrote:
> On 10/02/11 09:52, Helmut Grohne wrote:
> > Also I do wonder why the manual page for recv(2) does not list ENOBUFS
> > in the list of possible errors. Since posix[1] seems to specify it, it
> > looks like a bug in the manual page. *sigh*
> 
> This is quite netlink specific and nobody probably sent a patch for it
> so far. I encourage you to send a patch to the manpage maintainers. This
> is how things work, it's up to you to help others to fix this situation.

The reference [1] in my previous mail referenced
http://pubs.opengroup.org/onlinepubs/009695399/functions/recv.html.

Pablo, instead of complaining about missing patches, you could comment on the
other patch I sent in. I do send patches when I am confident that I understood
things. This just happens not to be the netfilter-log library.

Let me propose the addition at the end of this email to the recv(2) manual
page.

Helmut

--- recv.2.orig 2011-02-14 15:05:49.000000000 +0100
+++ recv.2      2011-02-14 15:26:13.000000000 +0100
@@ -425,6 +425,17 @@
 Invalid argument passed.
 .\" e.g., msg_namelen < 0 for recvmsg() or addrlen < 0 for recvfrom()
 .TP
+.B ENOBUFS
+A positive number of messages was dropped due to insufficient socket
+buffer space. On Linux this can occur when operating on netlink
+sockets. The
+.BR SO_RCVBUF
+and
+.BR SO_RCVBUFFORCE
+socket options described in
+.BR socket (7)
+can be used to change the socket buffer size.
+.TP
 .B ENOMEM
 Could not allocate memory for
 .BR recvmsg ().