bug#10404: [PATCH] Power: sleep longer than two seconds at a time

[Lars Ingebrigtsen <larsi@gnus.org>]

Glenn Morris <rgm@gnu.org> writes:

> Comments from Jan in
> http://lists.gnu.org/archive/html/emacs-devel/2013-07/msg00540.html
>
>     I don't know, I haven't seen this 2 second polling that is mentioned
>     (with strace/dtruss). When the cursor stops blinking, there is a 30
>     second timeout, and after that a very long timeout (thousands of
>     seconds, I don't have the exact value). But on the other hand, I was
>     not running Lisp at the time.
>
> I don't know where that leaves this patch.
> (See also comments in http://debbugs.gnu.org/10404#11 )

If I start "emacs -Q" and strace it, I see basically the following every
couple of seconds.

[pid  8439] --- SIGIO {si_signo=SIGIO, si_code=SI_KERNEL} ---
[pid  8439] rt_sigreturn()              = 1
[pid  8439] recvmsg(9, {msg_name(0)=NULL, msg_iov(1)=[{"\241 \33\f\263\0\340\3!\1\0\0.\1\0\0000\5\0\0\263\0\340\3\0\0\0\0\0\0\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
[pid  8439] recvmsg(9, 0x7ffda37f3120, 0) = -1 EAGAIN (Resource temporarily unavailable)
[pid  8439] poll([{fd=6, events=POLLIN}, {fd=8, events=POLLIN}, {fd=9, events=POLLIN}, {fd=13, events=POLLIN}], 4, 0) = 0 (Timeout)
[pid  8439] poll([{fd=6, events=POLLIN}, {fd=8, events=POLLIN}, {fd=9, events=POLLIN}, {fd=13, events=POLLIN}], 4, 0) = 0 (Timeout)
[pid  8439] poll([{fd=9, events=POLLIN|POLLOUT}], 1, 4294967295) = 1 ([{fd=9, revents=POLLOUT}])
[pid  8439] writev(9, [{"\31\0\v\0\366\0\0\0\0\0\30\0! \0\0\366\0\0\0!\1\0\0.\1\0\0000\5\0\0"..., 44}, {NULL, 0}, {"", 0}], 3) = 44
[pid  8439] recvmsg(9, 0x7ffda37f2ff0, 0) = -1 EAGAIN (Resource temporarily unavailable)
[pid  8439] recvmsg(9, 0x7ffda37f3120, 0) = -1 EAGAIN (Resource temporarily unavailable)
[pid  8439] poll([{fd=6, events=POLLIN}, {fd=8, events=POLLIN}, {fd=9, events=POLLIN}, {fd=13, events=POLLIN}], 4, 0) = 0 (Timeout)
[pid  8439] recvmsg(9, 0x7ffda37f3340, 0) = -1 EAGAIN (Resource temporarily unavailable)
[pid  8439] poll([{fd=6, events=POLLIN}, {fd=8, events=POLLIN}, {fd=9, events=POLLIN}, {fd=13, events=POLLIN}], 4, 0) = 0 (Timeout)
[pid  8439] pselect6(14, [6 8 9 13], [], NULL, {100000, 0}, {NULL, 8}) = 1 (in [9], left {99998, 551877999})

So something is polling and stuff on Linux, at least...

-- 
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   bloggy blog: http://lars.ingebrigtsen.no