We avoid the problem by using poll(2).
On systems without poll(2) (older bsd-ish systems, and win32), we emulate
poll(2) using select(2) and check for valid descriptors before attempting
to access them via the descriptor sets.
If an out-of-range descriptor is detected, an E_WARNING is raised suggesting
that PHP should be recompiled with a larger FD_SETSIZE (and also with a
suggested value).
Most uses of select(2) in the source are to poll a single descriptor, so
a couple of handy wrapper functions have been added to make this easier.
A configure option --enable-fd-setsize has been added to both the unix and
win32 builds; on unix we default to 16384 and on windows we default to 256.
Windows FD_SETSIZE imposes a limit on the maximum number of descriptors that
can be select()ed at once, whereas the unix FD_SETSIZE limit is based on the
highest numbered descriptor; 256 should be plenty for PHP scripts under windows
(the default OS setting is 64).
The win32 specific parts are untested; will do that now.
Big fat note: if you're building from a .dsp, you need to replicate
the custom build step that uses MC to generate the message catalog
To make use of this fix, you need to register the event source; running "nmake
install" will handle this for you (if you also build the win32std extension
from pecl).
I'll arrange with Phil to have the installer handle this registration too.
Be paranoid when building a snapshot: if the module is not a core
module (eg: it comes from outside of ext or sapi) and it defaults to "yes",
then force it to become shared. This will prevent a pecl ext from
accidentally being compiled statically into the core, and prevent that
ext from breaking the core build. You can still manually force a static
build by explicitly specifying the args for that extension on your configure
line.