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Comparing libev/ev.pod (file contents):
Revision 1.60 by root, Wed Nov 28 18:29:30 2007 UTC vs.
Revision 1.62 by root, Thu Nov 29 17:28:13 2007 UTC

… …
265or setgid) then libev will I<not> look at the environment variable 265or setgid) then libev will I<not> look at the environment variable
266C<LIBEV_FLAGS>. Otherwise (the default), this environment variable will 266C<LIBEV_FLAGS>. Otherwise (the default), this environment variable will
267override the flags completely if it is found in the environment. This is 267override the flags completely if it is found in the environment. This is
268useful to try out specific backends to test their performance, or to work 268useful to try out specific backends to test their performance, or to work
269around bugs. 269around bugs.
270
271=item C<EVFLAG_FORKCHECK>
272
273Instead of calling C<ev_default_fork> or C<ev_loop_fork> manually after
274a fork, you can also make libev check for a fork in each iteration by
275enabling this flag.
276
277This works by calling C<getpid ()> on every iteration of the loop,
278and thus this might slow down your event loop if you do a lot of loop
279iterations and little real work, but is usually not noticable (on my
280Linux system for example, C<getpid> is actually a simple 5-insn sequence
281without a syscall and thus I<very> fast, but my Linux system also has
282C<pthread_atfork> which is even faster).
283
284The big advantage of this flag is that you can forget about fork (and
285forget about forgetting to tell libev about forking) when you use this
286flag.
287
288This flag setting cannot be overriden or specified in the C<LIBEV_FLAGS>
289environment variable.
270 290
271=item C<EVBACKEND_SELECT> (value 1, portable select backend) 291=item C<EVBACKEND_SELECT> (value 1, portable select backend)
272 292
273This is your standard select(2) backend. Not I<completely> standard, as 293This is your standard select(2) backend. Not I<completely> standard, as
274libev tries to roll its own fd_set with no limits on the number of fds, 294libev tries to roll its own fd_set with no limits on the number of fds,
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916=item ev_timer_again (loop) 936=item ev_timer_again (loop)
917 937
918This will act as if the timer timed out and restart it again if it is 938This will act as if the timer timed out and restart it again if it is
919repeating. The exact semantics are: 939repeating. The exact semantics are:
920 940
941If the timer is pending, its pending status is cleared.
942
921If the timer is started but nonrepeating, stop it. 943If the timer is started but nonrepeating, stop it (as if it timed out).
922 944
923If the timer is repeating, either start it if necessary (with the repeat 945If the timer is repeating, either start it if necessary (with the
924value), or reset the running timer to the repeat value. 946C<repeat> value), or reset the running timer to the C<repeat> value.
925 947
926This sounds a bit complicated, but here is a useful and typical 948This sounds a bit complicated, but here is a useful and typical
927example: Imagine you have a tcp connection and you want a so-called 949example: Imagine you have a tcp connection and you want a so-called idle
928idle timeout, that is, you want to be called when there have been, 950timeout, that is, you want to be called when there have been, say, 60
929say, 60 seconds of inactivity on the socket. The easiest way to do 951seconds of inactivity on the socket. The easiest way to do this is to
930this is to configure an C<ev_timer> with C<after>=C<repeat>=C<60> and calling 952configure an C<ev_timer> with a C<repeat> value of C<60> and then call
931C<ev_timer_again> each time you successfully read or write some data. If 953C<ev_timer_again> each time you successfully read or write some data. If
932you go into an idle state where you do not expect data to travel on the 954you go into an idle state where you do not expect data to travel on the
933socket, you can stop the timer, and again will automatically restart it if 955socket, you can C<ev_timer_stop> the timer, and C<ev_timer_again> will
934need be. 956automatically restart it if need be.
935 957
936You can also ignore the C<after> value and C<ev_timer_start> altogether 958That means you can ignore the C<after> value and C<ev_timer_start>
937and only ever use the C<repeat> value: 959altogether and only ever use the C<repeat> value and C<ev_timer_again>:
938 960
939 ev_timer_init (timer, callback, 0., 5.); 961 ev_timer_init (timer, callback, 0., 5.);
940 ev_timer_again (loop, timer); 962 ev_timer_again (loop, timer);
941 ... 963 ...
942 timer->again = 17.; 964 timer->again = 17.;
943 ev_timer_again (loop, timer); 965 ev_timer_again (loop, timer);
944 ... 966 ...
945 timer->again = 10.; 967 timer->again = 10.;
946 ev_timer_again (loop, timer); 968 ev_timer_again (loop, timer);
947 969
948This is more efficient then stopping/starting the timer eahc time you want 970This is more slightly efficient then stopping/starting the timer each time
949to modify its timeout value. 971you want to modify its timeout value.
950 972
951=item ev_tstamp repeat [read-write] 973=item ev_tstamp repeat [read-write]
952 974
953The current C<repeat> value. Will be used each time the watcher times out 975The current C<repeat> value. Will be used each time the watcher times out
954or C<ev_timer_again> is called and determines the next timeout (if any), 976or C<ev_timer_again> is called and determines the next timeout (if any),

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