Re: listen(2) backlog

[email protected] (Christos Zoulas) Tue, 11 Nov 2025 17:44:07 -0000 (UTC)

Newsgroups	gmane.os.netbsd.devel.network
Message-ID	<[email protected]>

In article <[email protected]>,
Jan Schaumann  <[email protected]> wrote:
>Hello,
>
>listen(2) says that its 'backlog' parameter
>
>"defines the maximum length the queue of pending
>connections may grow to."
>
>It looks to me that in reality the length of the queue
>of pending complete connections ends up being backlog
>_plus one_ before incoming SYNs are ignored.
>
>Anybody know why that is?

Looks like:

    https://nxr.netbsd.org/xref/src/sys/kern/uipc_socket2.c#274

christos