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Comparing libev/ev.pod (file contents):
Revision 1.440 by root, Tue Jan 31 09:31:43 2017 UTC vs.
Revision 1.442 by root, Mon Jul 30 22:23:50 2018 UTC

411make libev check for a fork in each iteration by enabling this flag. 411make libev check for a fork in each iteration by enabling this flag.
412 412
413This works by calling C<getpid ()> on every iteration of the loop, 413This works by calling C<getpid ()> on every iteration of the loop,
414and thus this might slow down your event loop if you do a lot of loop 414and thus this might slow down your event loop if you do a lot of loop
415iterations and little real work, but is usually not noticeable (on my 415iterations and little real work, but is usually not noticeable (on my
416GNU/Linux system for example, C<getpid> is actually a simple 5-insn sequence 416GNU/Linux system for example, C<getpid> is actually a simple 5-insn
417without a system call and thus I<very> fast, but my GNU/Linux system also has 417sequence without a system call and thus I<very> fast, but my GNU/Linux
418C<pthread_atfork> which is even faster). 418system also has C<pthread_atfork> which is even faster). (Update: glibc
419versions 2.25 apparently removed the C<getpid> optimisation again).
419 420
420The big advantage of this flag is that you can forget about fork (and 421The big advantage of this flag is that you can forget about fork (and
421forget about forgetting to tell libev about forking, although you still 422forget about forgetting to tell libev about forking, although you still
422have to ignore C<SIGPIPE>) when you use this flag. 423have to ignore C<SIGPIPE>) when you use this flag.
423 424
3517 3518
3518There are some other functions of possible interest. Described. Here. Now. 3519There are some other functions of possible interest. Described. Here. Now.
3519 3520
3520=over 4 3521=over 4
3521 3522
3522=item ev_once (loop, int fd, int events, ev_tstamp timeout, callback) 3523=item ev_once (loop, int fd, int events, ev_tstamp timeout, callback, arg)
3523 3524
3524This function combines a simple timer and an I/O watcher, calls your 3525This function combines a simple timer and an I/O watcher, calls your
3525callback on whichever event happens first and automatically stops both 3526callback on whichever event happens first and automatically stops both
3526watchers. This is useful if you want to wait for a single event on an fd 3527watchers. This is useful if you want to wait for a single event on an fd
3527or timeout without having to allocate/configure/start/stop/free one or 3528or timeout without having to allocate/configure/start/stop/free one or

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