The accept4() function, compared to accept(), allows setting the new file
descriptor atomically close-on-exec and explicitly controlling the
non-blocking status on the new socket. (Note that the latter point means
that accept() is not equivalent to any form of accept4().)
The linuxulator's accept4 implementation leaves a race window where the new
file descriptor is not close-on-exec because it calls sys_accept(). This
implementation leaves no such race window (by using falloc() flags). The
linuxulator could be fixed and simplified by using the new code.
Like accept(), accept4() is async-signal-safe, a cancellation point and
permitted in capability mode.
While almost nobody uses O_ASYNC, and rightly so, the inheritance of the
related properties across accept() is a portability issue like the
inheritance of O_NONBLOCK.
negative (in addition to returning EINVAL when called on a descriptor
that is not a socket).
Submitted by: Arne H Juul <arnej@europe.yahoo-inc.com>
PR: docs/80587
no peer address information is desired.
PR: 56044
Submitted by: Felix Opatz <felix@zotteljedi.de> and
Bernd Luevelsmeyer <bdluevel@heitec.net>
MFC after: 1 month
Stop calling system calls "function calls".
Use "The .Fn system call" a-la "The .Nm utility".
When referring to a non-BSD implementation in
the HISTORY section, call syscall a function,
to be safe.
data without confirming the connection by issuing a recvmsg(2) [...]".
There's no such code in the kernel.
PR: 26861
Submitted by: Richard A Steenbergen <ras@e-gerbil.net>,
Tom Rhodes <darklogik@pittgoth.com>
with NetBSD and the Single Unix Specification v2.
This updates some structures with other, almost equivalent types and
effort is under way to get the whole more consistent.
Also removes a double definition of INET6 and some other clean-ups.
Reviewed by: green, bde, phk
Some part obtained from: NetBSD, SUSv2 specification
