… | |
… | |
411 | make libev check for a fork in each iteration by enabling this flag. |
411 | make libev check for a fork in each iteration by enabling this flag. |
412 | |
412 | |
413 | This works by calling C<getpid ()> on every iteration of the loop, |
413 | This works by calling C<getpid ()> on every iteration of the loop, |
414 | and thus this might slow down your event loop if you do a lot of loop |
414 | and thus this might slow down your event loop if you do a lot of loop |
415 | iterations and little real work, but is usually not noticeable (on my |
415 | iterations and little real work, but is usually not noticeable (on my |
416 | GNU/Linux system for example, C<getpid> is actually a simple 5-insn sequence |
416 | GNU/Linux system for example, C<getpid> is actually a simple 5-insn |
417 | without a system call and thus I<very> fast, but my GNU/Linux system also has |
417 | sequence without a system call and thus I<very> fast, but my GNU/Linux |
418 | C<pthread_atfork> which is even faster). |
418 | system also has C<pthread_atfork> which is even faster). (Update: glibc |
|
|
419 | versions 2.25 apparently removed the C<getpid> optimisation again). |
419 | |
420 | |
420 | The big advantage of this flag is that you can forget about fork (and |
421 | The big advantage of this flag is that you can forget about fork (and |
421 | forget about forgetting to tell libev about forking, although you still |
422 | forget about forgetting to tell libev about forking, although you still |
422 | have to ignore C<SIGPIPE>) when you use this flag. |
423 | have to ignore C<SIGPIPE>) when you use this flag. |
423 | |
424 | |
… | |
… | |
2209 | Periodic watchers are also timers of a kind, but they are very versatile |
2210 | Periodic watchers are also timers of a kind, but they are very versatile |
2210 | (and unfortunately a bit complex). |
2211 | (and unfortunately a bit complex). |
2211 | |
2212 | |
2212 | Unlike C<ev_timer>, periodic watchers are not based on real time (or |
2213 | Unlike C<ev_timer>, periodic watchers are not based on real time (or |
2213 | relative time, the physical time that passes) but on wall clock time |
2214 | relative time, the physical time that passes) but on wall clock time |
2214 | (absolute time, the thing you can read on your calender or clock). The |
2215 | (absolute time, the thing you can read on your calendar or clock). The |
2215 | difference is that wall clock time can run faster or slower than real |
2216 | difference is that wall clock time can run faster or slower than real |
2216 | time, and time jumps are not uncommon (e.g. when you adjust your |
2217 | time, and time jumps are not uncommon (e.g. when you adjust your |
2217 | wrist-watch). |
2218 | wrist-watch). |
2218 | |
2219 | |
2219 | You can tell a periodic watcher to trigger after some specific point |
2220 | You can tell a periodic watcher to trigger after some specific point |
… | |
… | |
4386 | ev_vars.h |
4387 | ev_vars.h |
4387 | ev_wrap.h |
4388 | ev_wrap.h |
4388 | |
4389 | |
4389 | ev_win32.c required on win32 platforms only |
4390 | ev_win32.c required on win32 platforms only |
4390 | |
4391 | |
4391 | ev_select.c only when select backend is enabled (which is enabled by default) |
4392 | ev_select.c only when select backend is enabled |
4392 | ev_poll.c only when poll backend is enabled (disabled by default) |
4393 | ev_poll.c only when poll backend is enabled |
4393 | ev_epoll.c only when the epoll backend is enabled (disabled by default) |
4394 | ev_epoll.c only when the epoll backend is enabled |
4394 | ev_kqueue.c only when the kqueue backend is enabled (disabled by default) |
4395 | ev_kqueue.c only when the kqueue backend is enabled |
4395 | ev_port.c only when the solaris port backend is enabled (disabled by default) |
4396 | ev_port.c only when the solaris port backend is enabled |
4396 | |
4397 | |
4397 | F<ev.c> includes the backend files directly when enabled, so you only need |
4398 | F<ev.c> includes the backend files directly when enabled, so you only need |
4398 | to compile this single file. |
4399 | to compile this single file. |
4399 | |
4400 | |
4400 | =head3 LIBEVENT COMPATIBILITY API |
4401 | =head3 LIBEVENT COMPATIBILITY API |
… | |
… | |
5300 | structure (guaranteed by POSIX but not by ISO C for example), but it also |
5301 | structure (guaranteed by POSIX but not by ISO C for example), but it also |
5301 | assumes that the same (machine) code can be used to call any watcher |
5302 | assumes that the same (machine) code can be used to call any watcher |
5302 | callback: The watcher callbacks have different type signatures, but libev |
5303 | callback: The watcher callbacks have different type signatures, but libev |
5303 | calls them using an C<ev_watcher *> internally. |
5304 | calls them using an C<ev_watcher *> internally. |
5304 | |
5305 | |
|
|
5306 | =item null pointers and integer zero are represented by 0 bytes |
|
|
5307 | |
|
|
5308 | Libev uses C<memset> to initialise structs and arrays to C<0> bytes, and |
|
|
5309 | relies on this setting pointers and integers to null. |
|
|
5310 | |
5305 | =item pointer accesses must be thread-atomic |
5311 | =item pointer accesses must be thread-atomic |
5306 | |
5312 | |
5307 | Accessing a pointer value must be atomic, it must both be readable and |
5313 | Accessing a pointer value must be atomic, it must both be readable and |
5308 | writable in one piece - this is the case on all current architectures. |
5314 | writable in one piece - this is the case on all current architectures. |
5309 | |
5315 | |