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Subjectpaccept() oddity
From
Ulrich,

[
2.6.27-rc has paccept():

int paccept(int fd, struct sockaddr *sockaddr, socklen_t *addrlen,
const sigset_t *sigmask, int setsize, int flags)
]

While considering the sigset argument for paccept() (see my previous
message), and testing that system call, I realized that there is a certain
oddness in the implementation of paccept().

Like accept(), paccept() automatically restarts if interrupted by a signal
handler that was established with the SA_RESTART flag.

On the other hand, pselect(), ppoll(), and epoll_pwait() are never restarted
if interrupted by a handler, even if the handler was established with
SA_RESTART. (This is the same as with select(), poll(), and epoll_wait().)

It seems to me that it makes little sense to restart paccept(), especially in
the case where it is interrupted by a handler for one of the signals that is
in sigmask, since the whole point of calling paccept() is to block until a
connection is received, or until one of the signals in sigmask is caught().

How about changing paccept() so that it is never automatically restarted if
interrupted by a signal handler, regardless of the SA_RESTART flag. (In
other words, paccept() should be consistent with pselect(), ppoll(), and
epoll_pwait(), rather than being consistent with accept().) What are your
thoughts?

Cheers,

Michael



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