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Comparing libev/ev.pod (file contents):
Revision 1.61 by root, Thu Nov 29 12:21:05 2007 UTC vs.
Revision 1.66 by root, Mon Dec 3 13:41:25 2007 UTC

… …
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.
270 270
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 noticeable (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.
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,
275but if that fails, expect a fairly low limit on the number of fds when 295but if that fails, expect a fairly low limit on the number of fds when
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409=item ev_loop_fork (loop) 429=item ev_loop_fork (loop)
410 430
411Like C<ev_default_fork>, but acts on an event loop created by 431Like C<ev_default_fork>, but acts on an event loop created by
412C<ev_loop_new>. Yes, you have to call this on every allocated event loop 432C<ev_loop_new>. Yes, you have to call this on every allocated event loop
413after fork, and how you do this is entirely your own problem. 433after fork, and how you do this is entirely your own problem.
434
435=item unsigned int ev_loop_count (loop)
436
437Returns the count of loop iterations for the loop, which is identical to
438the number of times libev did poll for new events. It starts at C<0> and
439happily wraps around with enough iterations.
440
441This value can sometimes be useful as a generation counter of sorts (it
442"ticks" the number of loop iterations), as it roughly corresponds with
443C<ev_prepare> and C<ev_check> calls.
414 444
415=item unsigned int ev_backend (loop) 445=item unsigned int ev_backend (loop)
416 446
417Returns one of the C<EVBACKEND_*> flags indicating the event backend in 447Returns one of the C<EVBACKEND_*> flags indicating the event backend in
418use. 448use.
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1437 1467
1438 // create io watchers for each fd and a timer before blocking 1468 // create io watchers for each fd and a timer before blocking
1439 static void 1469 static void
1440 adns_prepare_cb (ev_loop *loop, ev_prepare *w, int revents) 1470 adns_prepare_cb (ev_loop *loop, ev_prepare *w, int revents)
1441 { 1471 {
1442 int timeout = 3600000;truct pollfd fds [nfd]; 1472 int timeout = 3600000;
1473 struct pollfd fds [nfd];
1443 // actual code will need to loop here and realloc etc. 1474 // actual code will need to loop here and realloc etc.
1444 adns_beforepoll (ads, fds, &nfd, &timeout, timeval_from (ev_time ())); 1475 adns_beforepoll (ads, fds, &nfd, &timeout, timeval_from (ev_time ()));
1445 1476
1446 /* the callback is illegal, but won't be called as we stop during check */ 1477 /* the callback is illegal, but won't be called as we stop during check */
1447 ev_timer_init (&tw, 0, timeout * 1e-3); 1478 ev_timer_init (&tw, 0, timeout * 1e-3);
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1828Similar to the other two macros, this gives you the value of the default 1859Similar to the other two macros, this gives you the value of the default
1829loop, if multiple loops are supported ("ev loop default"). 1860loop, if multiple loops are supported ("ev loop default").
1830 1861
1831=back 1862=back
1832 1863
1833Example: Declare and initialise a check watcher, working regardless of 1864Example: Declare and initialise a check watcher, utilising the above
1834wether multiple loops are supported or not. 1865macros so it will work regardless of wether multiple loops are supported
1866or not.
1835 1867
1836 static void 1868 static void
1837 check_cb (EV_P_ ev_timer *w, int revents) 1869 check_cb (EV_P_ ev_timer *w, int revents)
1838 { 1870 {
1839 ev_check_stop (EV_A_ w); 1871 ev_check_stop (EV_A_ w);
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1841 1873
1842 ev_check check; 1874 ev_check check;
1843 ev_check_init (&check, check_cb); 1875 ev_check_init (&check, check_cb);
1844 ev_check_start (EV_DEFAULT_ &check); 1876 ev_check_start (EV_DEFAULT_ &check);
1845 ev_loop (EV_DEFAULT_ 0); 1877 ev_loop (EV_DEFAULT_ 0);
1846
1847 1878
1848=head1 EMBEDDING 1879=head1 EMBEDDING
1849 1880
1850Libev can (and often is) directly embedded into host 1881Libev can (and often is) directly embedded into host
1851applications. Examples of applications that embed it include the Deliantra 1882applications. Examples of applications that embed it include the Deliantra
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1891 ev_vars.h 1922 ev_vars.h
1892 ev_wrap.h 1923 ev_wrap.h
1893 1924
1894 ev_win32.c required on win32 platforms only 1925 ev_win32.c required on win32 platforms only
1895 1926
1896 ev_select.c only when select backend is enabled (which is by default) 1927 ev_select.c only when select backend is enabled (which is enabled by default)
1897 ev_poll.c only when poll backend is enabled (disabled by default) 1928 ev_poll.c only when poll backend is enabled (disabled by default)
1898 ev_epoll.c only when the epoll backend is enabled (disabled by default) 1929 ev_epoll.c only when the epoll backend is enabled (disabled by default)
1899 ev_kqueue.c only when the kqueue backend is enabled (disabled by default) 1930 ev_kqueue.c only when the kqueue backend is enabled (disabled by default)
1900 ev_port.c only when the solaris port backend is enabled (disabled by default) 1931 ev_port.c only when the solaris port backend is enabled (disabled by default)
1901 1932
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2143interface) and F<EV.xs> (implementation) files. Only the F<EV.xs> file 2174interface) and F<EV.xs> (implementation) files. Only the F<EV.xs> file
2144will be compiled. It is pretty complex because it provides its own header 2175will be compiled. It is pretty complex because it provides its own header
2145file. 2176file.
2146 2177
2147The usage in rxvt-unicode is simpler. It has a F<ev_cpp.h> header file 2178The usage in rxvt-unicode is simpler. It has a F<ev_cpp.h> header file
2148that everybody includes and which overrides some autoconf choices: 2179that everybody includes and which overrides some configure choices:
2149 2180
2181 #define EV_MINIMAL 1
2150 #define EV_USE_POLL 0 2182 #define EV_USE_POLL 0
2151 #define EV_MULTIPLICITY 0 2183 #define EV_MULTIPLICITY 0
2152 #define EV_PERIODICS 0 2184 #define EV_PERIODIC_ENABLE 0
2185 #define EV_STAT_ENABLE 0
2186 #define EV_FORK_ENABLE 0
2153 #define EV_CONFIG_H <config.h> 2187 #define EV_CONFIG_H <config.h>
2188 #define EV_MINPRI 0
2189 #define EV_MAXPRI 0
2154 2190
2155 #include "ev++.h" 2191 #include "ev++.h"
2156 2192
2157And a F<ev_cpp.C> implementation file that contains libev proper and is compiled: 2193And a F<ev_cpp.C> implementation file that contains libev proper and is compiled:
2158 2194

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