[PATCH 10/24] man/man7/unix.7: SIOCINQ: Document behavior for SOCK_SEQPACKET

["Günther Noack" <gnoack3000@gmail.com>]

unix_inq_len() in linux.git net/unix/af_unix.c handles all of
SOCK_SOCKET, SOCK_DGRAM and also SOCK_SEQPACKET

* Document SOCK_SEQPACKET, which sums up the lengths of all messages
  in the receive queue.
* Restructure sentence order, so that socket type differences are
  discussed in on paragraph, and commonalities in the next.

Assisted-by: LLM
Signed-off-by: Günther Noack <gnoack3000@gmail.com>
---

Notes:
    Double checked in code:
    
    unix_inq_len() first rejects listening sockets, then has a case
    analysis for the three socket types.
    
    The LLM initially just slapped an additional sentence into the
    paragraph, but that was mixing the socket-type-specific concerns with
    the general description -- I split that paragraph apart so that we
    have one paragraph for the three socket types and one for the
    socket-type-independent description.

 man/man7/unix.7 | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/man/man7/unix.7 b/man/man7/unix.7
index 8fd29131ce48..4d431ec6deaf 100644
--- a/man/man7/unix.7
+++ b/man/man7/unix.7
@@ -606,6 +606,19 @@ can be:
 For
 .B SOCK_STREAM
 sockets, this call returns the number of unread bytes in the receive buffer.
+For
+.B SOCK_DGRAM
+sockets,
+the returned value is the same as
+for Internet domain datagram sockets;
+see
+.BR udp (7).
+For
+.B SOCK_SEQPACKET
+sockets,
+this call returns the total number of bytes
+in all messages queued in the receive buffer.
+.IP
 The socket must not be in LISTEN state, otherwise an error
 .RB ( EINVAL )
 is returned.
@@ -625,13 +638,6 @@ defined in
 .\" That number is normally larger than the number of bytes of pending
 .\" output.  Since this info is, from userland's point of view, imprecise,
 .\" and it may well change, probably best not to document this now.
-For
-.B SOCK_DGRAM
-sockets,
-the returned value is the same as
-for Internet domain datagram sockets;
-see
-.BR udp (7).
 .SH ERRORS
 .TP
 .B EADDRINUSE
-- 
2.56.0