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Comparing libev/ev.pod (file contents):
Revision 1.313 by root, Fri Oct 22 05:44:33 2010 UTC vs.
Revision 1.314 by root, Fri Oct 22 06:06:31 2010 UTC

… …
4531=head3 C<kqueue> is buggy 4531=head3 C<kqueue> is buggy
4532 4532
4533The kqueue syscall is broken in all known versions - most versions support 4533The kqueue syscall is broken in all known versions - most versions support
4534only sockets, many support pipes. 4534only sockets, many support pipes.
4535 4535
4536Libev tries to work around this by not using C<kqueue> by default on 4536Libev tries to work around this by not using C<kqueue> by default on this
4537this rotten platform, but of course you can still ask for it when creating 4537rotten platform, but of course you can still ask for it when creating a
4538a loop. 4538loop - embedding a socket-only kqueue loop into a select-based one is
4539probably going to work well.
4539 4540
4540=head3 C<poll> is buggy 4541=head3 C<poll> is buggy
4541 4542
4542Instead of fixing C<kqueue>, Apple replaced their (working) C<poll> 4543Instead of fixing C<kqueue>, Apple replaced their (working) C<poll>
4543implementation by something calling C<kqueue> internally around the 10.5.6 4544implementation by something calling C<kqueue> internally around the 10.5.6
… …
4562 4563
4563=head3 C<errno> reentrancy 4564=head3 C<errno> reentrancy
4564 4565
4565The default compile environment on Solaris is unfortunately so 4566The default compile environment on Solaris is unfortunately so
4566thread-unsafe that you can't even use components/libraries compiled 4567thread-unsafe that you can't even use components/libraries compiled
4567without C<-D_REENTRANT> (as long as they use C<errno>), which, of course, 4568without C<-D_REENTRANT> in a threaded program, which, of course, isn't
4568isn't defined by default. 4569defined by default. A valid, if stupid, implementation choice.
4569 4570
4570If you want to use libev in threaded environments you have to make sure 4571If you want to use libev in threaded environments you have to make sure
4571it's compiled with C<_REENTRANT> defined. 4572it's compiled with C<_REENTRANT> defined.
4572 4573
4573=head3 Event port backend 4574=head3 Event port backend
4574 4575
4575The scalable event interface for Solaris is called "event ports". Unfortunately, 4576The scalable event interface for Solaris is called "event
4576this mechanism is very buggy. If you run into high CPU usage, your program 4577ports". Unfortunately, this mechanism is very buggy in all major
4578releases. If you run into high CPU usage, your program freezes or you get
4577freezes or you get a large number of spurious wakeups, make sure you have 4579a large number of spurious wakeups, make sure you have all the relevant
4578all the relevant and latest kernel patches applied. No, I don't know which 4580and latest kernel patches applied. No, I don't know which ones, but there
4579ones, but there are multiple ones. 4581are multiple ones to apply, and afterwards, event ports actually work
4582great.
4580 4583
4581If you can't get it to work, you can try running the program by setting 4584If you can't get it to work, you can try running the program by setting
4582the environment variable C<LIBEV_FLAGS=3> to only allow C<poll> and 4585the environment variable C<LIBEV_FLAGS=3> to only allow C<poll> and
4583C<select> backends. 4586C<select> backends.
4584 4587
4585=head2 AIX POLL BUG 4588=head2 AIX POLL BUG
4586 4589
4587AIX unfortunately has a broken C<poll.h> header. Libev works around 4590AIX unfortunately has a broken C<poll.h> header. Libev works around
4588this by trying to avoid the poll backend altogether (i.e. it's not even 4591this by trying to avoid the poll backend altogether (i.e. it's not even
4589compiled in), which normally isn't a big problem as C<select> works fine 4592compiled in), which normally isn't a big problem as C<select> works fine
4590with large bitsets, and AIX is dead anyway. 4593with large bitsets on AIX, and AIX is dead anyway.
4591 4594
4592=head2 WIN32 PLATFORM LIMITATIONS AND WORKAROUNDS 4595=head2 WIN32 PLATFORM LIMITATIONS AND WORKAROUNDS
4593 4596
4594=head3 General issues 4597=head3 General issues
4595 4598

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