From 924ae10c0376cdb4b581d30f7b8a258b6b9e4853 Mon Sep 17 00:00:00 2001 From: root Date: Tue, 27 Nov 2007 20:26:50 +0000 Subject: *** empty log message *** --- ev.3 | 92 +++++++++++++++++++++++++--------------------- ev.html | 128 ++++++++++++++++++++++++++++++++++------------------------------ ev.pod | 87 +++++++++++++++++++++++-------------------- 3 files changed, 166 insertions(+), 141 deletions(-) diff --git a/ev.3 b/ev.3 index 6c36997..a2e0946 100644 --- a/ev.3 +++ b/ev.3 @@ -134,13 +134,16 @@ libev \- a high performance full\-featured event loop written in C .SH "SYNOPSIS" .IX Header "SYNOPSIS" -.Vb 2 -\& /* this is the only header you need */ +.Vb 1 +\& #include +.Ve +.SH "EXAMPLE PROGRAM" +.IX Header "EXAMPLE PROGRAM" +.Vb 1 \& #include .Ve .PP -.Vb 3 -\& /* what follows is a fully working example program */ +.Vb 2 \& ev_io stdin_watcher; \& ev_timer timeout_watcher; .Ve @@ -209,22 +212,27 @@ details of the event, and then hand it over to libev by \fIstarting\fR the watcher. .SH "FEATURES" .IX Header "FEATURES" -Libev supports select, poll, the linux-specific epoll and the bsd-specific -kqueue mechanisms for file descriptor events, relative timers, absolute -timers with customised rescheduling, signal events, process status change -events (related to \s-1SIGCHLD\s0), and event watchers dealing with the event -loop mechanism itself (idle, prepare and check watchers). It also is quite -fast (see this benchmark comparing -it to libevent for example). +Libev supports \f(CW\*(C`select\*(C'\fR, \f(CW\*(C`poll\*(C'\fR, the linux-specific \f(CW\*(C`epoll\*(C'\fR, the +bsd-specific \f(CW\*(C`kqueue\*(C'\fR and the solaris-specific event port mechanisms +for file descriptor events (\f(CW\*(C`ev_io\*(C'\fR), relative timers (\f(CW\*(C`ev_timer\*(C'\fR), +absolute timers with customised rescheduling (\f(CW\*(C`ev_periodic\*(C'\fR), synchronous +signals (\f(CW\*(C`ev_signal\*(C'\fR), process status change events (\f(CW\*(C`ev_child\*(C'\fR), and +event watchers dealing with the event loop mechanism itself (\f(CW\*(C`ev_idle\*(C'\fR, +\&\f(CW\*(C`ev_embed\*(C'\fR, \f(CW\*(C`ev_prepare\*(C'\fR and \f(CW\*(C`ev_check\*(C'\fR watchers) as well as +file watchers (\f(CW\*(C`ev_stat\*(C'\fR) and even limited support for fork events +(\f(CW\*(C`ev_fork\*(C'\fR). +.PP +It also is quite fast (see this +benchmark comparing it to libevent +for example). .SH "CONVENTIONS" .IX Header "CONVENTIONS" -Libev is very configurable. In this manual the default configuration -will be described, which supports multiple event loops. For more info -about various configuration options please have a look at the file -\&\fI\s-1README\s0.embed\fR in the libev distribution. If libev was configured without -support for multiple event loops, then all functions taking an initial -argument of name \f(CW\*(C`loop\*(C'\fR (which is always of type \f(CW\*(C`struct ev_loop *\*(C'\fR) -will not have this argument. +Libev is very configurable. In this manual the default configuration will +be described, which supports multiple event loops. For more info about +various configuration options please have a look at \fB\s-1EMBED\s0\fR section in +this manual. If libev was configured without support for multiple event +loops, then all functions taking an initial argument of name \f(CW\*(C`loop\*(C'\fR +(which is always of type \f(CW\*(C`struct ev_loop *\*(C'\fR) will not have this argument. .SH "TIME REPRESENTATION" .IX Header "TIME REPRESENTATION" Libev represents time as a single floating point number, representing the @@ -259,8 +267,8 @@ as this indicates an incompatible change. Minor versions are usually compatible to older versions, so a larger minor version alone is usually not a problem. .Sp -Example: make sure we haven't accidentally been linked against the wrong -version: +Example: Make sure we haven't accidentally been linked against the wrong +version. .Sp .Vb 3 \& assert (("libev version mismatch", @@ -310,8 +318,8 @@ You could override this function in high-availability programs to, say, free some memory if it cannot allocate memory, to use a special allocator, or even to sleep a while and retry until some memory is available. .Sp -Example: replace the libev allocator with one that waits a bit and then -retries: better than mine). +Example: Replace the libev allocator with one that waits a bit and then +retries). .Sp .Vb 6 \& static void * @@ -347,7 +355,7 @@ matter what, when it returns. That is, libev will generally retry the requested operation, or, if the condition doesn't go away, do bad stuff (such as abort). .Sp -Example: do the same thing as libev does internally: +Example: This is basically the same thing that libev does internally, too. .Sp .Vb 6 \& static void @@ -506,7 +514,7 @@ always distinct from the default loop. Unlike the default loop, it cannot handle signal and child watchers, and attempts to do so will be greeted by undefined behaviour (or a failed assertion if assertions are enabled). .Sp -Example: try to create a event loop that uses epoll and nothing else. +Example: Try to create a event loop that uses epoll and nothing else. .Sp .Vb 3 \& struct ev_loop *epoller = ev_loop_new (EVBACKEND_EPOLL | EVFLAG_NOENV); @@ -614,7 +622,7 @@ Here are the gory details of what \f(CW\*(C`ev_loop\*(C'\fR does: \& were used, return, otherwise continue with step *. .Ve .Sp -Example: queue some jobs and then loop until no events are outsanding +Example: Queue some jobs and then loop until no events are outsanding anymore. .Sp .Vb 4 @@ -646,21 +654,21 @@ no event watchers registered by it are active. It is also an excellent way to do this for generic recurring timers or from within third-party libraries. Just remember to \fIunref after start\fR and \fIref before stop\fR. .Sp -Example: create a signal watcher, but keep it from keeping \f(CW\*(C`ev_loop\*(C'\fR +Example: Create a signal watcher, but keep it from keeping \f(CW\*(C`ev_loop\*(C'\fR running when nothing else is active. .Sp .Vb 4 -\& struct dv_signal exitsig; +\& struct ev_signal exitsig; \& ev_signal_init (&exitsig, sig_cb, SIGINT); -\& ev_signal_start (myloop, &exitsig); -\& evf_unref (myloop); +\& ev_signal_start (loop, &exitsig); +\& evf_unref (loop); .Ve .Sp -Example: for some weird reason, unregister the above signal handler again. +Example: For some weird reason, unregister the above signal handler again. .Sp .Vb 2 -\& ev_ref (myloop); -\& ev_signal_stop (myloop, &exitsig); +\& ev_ref (loop); +\& ev_signal_stop (loop, &exitsig); .Ve .SH "ANATOMY OF A WATCHER" .IX Header "ANATOMY OF A WATCHER" @@ -959,9 +967,9 @@ The file descriptor being watched. .IX Item "int events [read-only]" The events being watched. .PP -Example: call \f(CW\*(C`stdin_readable_cb\*(C'\fR when \s-1STDIN_FILENO\s0 has become, well +Example: Call \f(CW\*(C`stdin_readable_cb\*(C'\fR when \s-1STDIN_FILENO\s0 has become, well readable, but only once. Since it is likely line\-buffered, you could -attempt to read a whole line in the callback: +attempt to read a whole line in the callback. .PP .Vb 6 \& static void @@ -1063,7 +1071,7 @@ The current \f(CW\*(C`repeat\*(C'\fR value. Will be used each time the watcher t or \f(CW\*(C`ev_timer_again\*(C'\fR is called and determines the next timeout (if any), which is also when any modifications are taken into account. .PP -Example: create a timer that fires after 60 seconds. +Example: Create a timer that fires after 60 seconds. .PP .Vb 5 \& static void @@ -1079,7 +1087,7 @@ Example: create a timer that fires after 60 seconds. \& ev_timer_start (loop, &mytimer); .Ve .PP -Example: create a timeout timer that times out after 10 seconds of +Example: Create a timeout timer that times out after 10 seconds of inactivity. .PP .Vb 5 @@ -1214,7 +1222,7 @@ The current reschedule callback, or \f(CW0\fR, if this functionality is switched off. Can be changed any time, but changes only take effect when the periodic timer fires or \f(CW\*(C`ev_periodic_again\*(C'\fR is being called. .PP -Example: call a callback every hour, or, more precisely, whenever the +Example: Call a callback every hour, or, more precisely, whenever the system clock is divisible by 3600. The callback invocation times have potentially a lot of jittering, but good long-term stability. .PP @@ -1232,7 +1240,7 @@ potentially a lot of jittering, but good long-term stability. \& ev_periodic_start (loop, &hourly_tick); .Ve .PP -Example: the same as above, but use a reschedule callback to do it: +Example: The same as above, but use a reschedule callback to do it: .PP .Vb 1 \& #include @@ -1250,7 +1258,7 @@ Example: the same as above, but use a reschedule callback to do it: \& ev_periodic_init (&hourly_tick, clock_cb, 0., 0., my_scheduler_cb); .Ve .PP -Example: call a callback every hour, starting now: +Example: Call a callback every hour, starting now: .PP .Vb 4 \& struct ev_periodic hourly_tick; @@ -1311,7 +1319,7 @@ The process id that detected a status change. The process exit/trace status caused by \f(CW\*(C`rpid\*(C'\fR (see your systems \&\f(CW\*(C`waitpid\*(C'\fR and \f(CW\*(C`sys/wait.h\*(C'\fR documentation for details). .PP -Example: try to exit cleanly on \s-1SIGINT\s0 and \s-1SIGTERM\s0. +Example: Try to exit cleanly on \s-1SIGINT\s0 and \s-1SIGTERM\s0. .PP .Vb 5 \& static void @@ -1445,8 +1453,8 @@ Initialises and configures the idle watcher \- it has no parameters of any kind. There is a \f(CW\*(C`ev_idle_set\*(C'\fR macro, but using it is utterly pointless, believe me. .PP -Example: dynamically allocate an \f(CW\*(C`ev_idle\*(C'\fR, start it, and in the -callback, free it. Alos, use no error checking, as usual. +Example: Dynamically allocate an \f(CW\*(C`ev_idle\*(C'\fR watcher, start it, and in the +callback, free it. Also, use no error checking, as usual. .PP .Vb 7 \& static void diff --git a/ev.html b/ev.html index bb4c00e..bb85c18 100644 --- a/ev.html +++ b/ev.html @@ -6,7 +6,7 @@ - + @@ -16,6 +16,7 @@
-

NAME

Top

+

NAME

libev - a high performance full-featured event loop written in C

-

SYNOPSIS

Top

+

SYNOPSIS

-
  /* this is the only header you need */
-  #include <ev.h>
+
  #include <ev.h>
+
+
+ +
+

EXAMPLE PROGRAM

+
+
  #include <ev.h>
 
-  /* what follows is a fully working example program */
   ev_io stdin_watcher;
   ev_timer timeout_watcher;
 
@@ -113,7 +119,7 @@
 
-

DESCRIPTION

Top

+

DESCRIPTION

Libev is an event loop: you register interest in certain events (such as a file descriptor being readable or a timeout occuring), and it will manage @@ -127,29 +133,33 @@ details of the event, and then hand it over to libev by starting the watcher.

-

FEATURES

Top

+

FEATURES

-

Libev supports select, poll, the linux-specific epoll and the bsd-specific -kqueue mechanisms for file descriptor events, relative timers, absolute -timers with customised rescheduling, signal events, process status change -events (related to SIGCHLD), and event watchers dealing with the event -loop mechanism itself (idle, prepare and check watchers). It also is quite -fast (see this benchmark comparing -it to libevent for example).

+

Libev supports select, poll, the linux-specific epoll, the +bsd-specific kqueue and the solaris-specific event port mechanisms +for file descriptor events (ev_io), relative timers (ev_timer), +absolute timers with customised rescheduling (ev_periodic), synchronous +signals (ev_signal), process status change events (ev_child), and +event watchers dealing with the event loop mechanism itself (ev_idle, +ev_embed, ev_prepare and ev_check watchers) as well as +file watchers (ev_stat) and even limited support for fork events +(ev_fork).

+

It also is quite fast (see this +benchmark comparing it to libevent +for example).

-

CONVENTIONS

Top

+

CONVENTIONS

-

Libev is very configurable. In this manual the default configuration -will be described, which supports multiple event loops. For more info -about various configuration options please have a look at the file -README.embed in the libev distribution. If libev was configured without -support for multiple event loops, then all functions taking an initial -argument of name loop (which is always of type struct ev_loop *) -will not have this argument.

+

Libev is very configurable. In this manual the default configuration will +be described, which supports multiple event loops. For more info about +various configuration options please have a look at EMBED section in +this manual. If libev was configured without support for multiple event +loops, then all functions taking an initial argument of name loop +(which is always of type struct ev_loop *) will not have this argument.

-

TIME REPRESENTATION

Top

+

TIME REPRESENTATION

Libev represents time as a single floating point number, representing the (fractional) number of seconds since the (POSIX) epoch (somewhere near @@ -159,7 +169,7 @@ to the double type in C, and when you need to do any calculations o it, you should treat it as such.

-

GLOBAL FUNCTIONS

Top

+

GLOBAL FUNCTIONS

These functions can be called anytime, even before initialising the library in any way.

@@ -182,8 +192,8 @@ version of the library your program was compiled against.

as this indicates an incompatible change. Minor versions are usually compatible to older versions, so a larger minor version alone is usually not a problem.

-

Example: make sure we haven't accidentally been linked against the wrong -version:

+

Example: Make sure we haven't accidentally been linked against the wrong +version.

  assert (("libev version mismatch",
            ev_version_major () == EV_VERSION_MAJOR
            && ev_version_minor () >= EV_VERSION_MINOR));
@@ -231,8 +241,8 @@ action. The default is your system realloc function.

You could override this function in high-availability programs to, say, free some memory if it cannot allocate memory, to use a special allocator, or even to sleep a while and retry until some memory is available.

-

Example: replace the libev allocator with one that waits a bit and then -retries: better than mine).

+

Example: Replace the libev allocator with one that waits a bit and then +retries).

   static void *
    persistent_realloc (void *ptr, size_t size)
    {
@@ -261,7 +271,7 @@ callback is set, then libev will expect it to remedy the sitution, no
 matter what, when it returns. That is, libev will generally retry the
 requested operation, or, if the condition doesn't go away, do bad stuff
 (such as abort).

-

Example: do the same thing as libev does internally:

+

Example: This is basically the same thing that libev does internally, too.

   static void
    fatal_error (const char *msg)
    {
@@ -277,7 +287,7 @@ requested operation, or, if the condition doesn't go away, do bad stuff
 
 
 
-

FUNCTIONS CONTROLLING THE EVENT LOOP

Top

+

FUNCTIONS CONTROLLING THE EVENT LOOP

An event loop is described by a struct ev_loop *. The library knows two types of such loops, the default loop, which supports signals and child @@ -407,7 +417,7 @@ event loop and only if you know the OS supports your types of fds):

always distinct from the default loop. Unlike the default loop, it cannot handle signal and child watchers, and attempts to do so will be greeted by undefined behaviour (or a failed assertion if assertions are enabled).

-

Example: try to create a event loop that uses epoll and nothing else.

+

Example: Try to create a event loop that uses epoll and nothing else.

  struct ev_loop *epoller = ev_loop_new (EVBACKEND_EPOLL | EVFLAG_NOENV);
   if (!epoller)
     fatal ("no epoll found here, maybe it hides under your chair");
@@ -510,7 +520,7 @@ usually a better approach for this kind of thing.

were used, return, otherwise continue with step *.
-

Example: queue some jobs and then loop until no events are outsanding +

Example: Queue some jobs and then loop until no events are outsanding anymore.

   ... queue jobs here, make sure they register event watchers as long
    ... as they still have work to do (even an idle watcher will do..)
@@ -539,17 +549,17 @@ visible to the libev user and should not keep ev_loop from exiting
 no event watchers registered by it are active. It is also an excellent
 way to do this for generic recurring timers or from within third-party
 libraries. Just remember to unref after start and ref before stop.

-

Example: create a signal watcher, but keep it from keeping ev_loop +

Example: Create a signal watcher, but keep it from keeping ev_loop running when nothing else is active.

-
  struct dv_signal exitsig;
+
  struct ev_signal exitsig;
   ev_signal_init (&exitsig, sig_cb, SIGINT);
-  ev_signal_start (myloop, &exitsig);
-  evf_unref (myloop);
+  ev_signal_start (loop, &exitsig);
+  evf_unref (loop);
 
 
-

Example: for some weird reason, unregister the above signal handler again.

-
  ev_ref (myloop);
-  ev_signal_stop (myloop, &exitsig);
+		

Example: For some weird reason, unregister the above signal handler again.

+
  ev_ref (loop);
+  ev_signal_stop (loop, &exitsig);
 
 
@@ -560,7 +570,7 @@ running when nothing else is active.

-

ANATOMY OF A WATCHER

Top

+

ANATOMY OF A WATCHER

A watcher is a structure that you create and register to record your interest in some event. For instance, if you want to wait for STDIN to @@ -783,7 +793,7 @@ have been omitted....

-

WATCHER TYPES

Top

+

WATCHER TYPES

This section describes each watcher in detail, but will not repeat information given in the last section. Any initialisation/set macros, @@ -853,9 +863,9 @@ rceeive events for and events is either EV_READ, EV_WRITEThe events being watched.

-

Example: call stdin_readable_cb when STDIN_FILENO has become, well +

Example: Call stdin_readable_cb when STDIN_FILENO has become, well readable, but only once. Since it is likely line-buffered, you could -attempt to read a whole line in the callback:

+attempt to read a whole line in the callback.

  static void
   stdin_readable_cb (struct ev_loop *loop, struct ev_io *w, int revents)
   {
@@ -948,7 +958,7 @@ or ev_timer_again is called and determines the next timeout (if any
 which is also when any modifications are taken into account.

-

Example: create a timer that fires after 60 seconds.

+

Example: Create a timer that fires after 60 seconds.

  static void
   one_minute_cb (struct ev_loop *loop, struct ev_timer *w, int revents)
   {
@@ -960,7 +970,7 @@ which is also when any modifications are taken into account.

ev_timer_start (loop, &mytimer);
-

Example: create a timeout timer that times out after 10 seconds of +

Example: Create a timeout timer that times out after 10 seconds of inactivity.

  static void
   timeout_cb (struct ev_loop *loop, struct ev_timer *w, int revents)
@@ -1086,7 +1096,7 @@ switched off. Can be changed any time, but changes only take effect when
 the periodic timer fires or ev_periodic_again is being called.

-

Example: call a callback every hour, or, more precisely, whenever the +

Example: Call a callback every hour, or, more precisely, whenever the system clock is divisible by 3600. The callback invocation times have potentially a lot of jittering, but good long-term stability.

  static void
@@ -1100,7 +1110,7 @@ potentially a lot of jittering, but good long-term stability.

ev_periodic_start (loop, &hourly_tick);
-

Example: the same as above, but use a reschedule callback to do it:

+

Example: The same as above, but use a reschedule callback to do it:

  #include <math.h>
 
   static ev_tstamp
@@ -1112,7 +1122,7 @@ potentially a lot of jittering, but good long-term stability.

ev_periodic_init (&hourly_tick, clock_cb, 0., 0., my_scheduler_cb);
-

Example: call a callback every hour, starting now:

+

Example: Call a callback every hour, starting now:

  struct ev_periodic hourly_tick;
   ev_periodic_init (&hourly_tick, clock_cb,
                     fmod (ev_now (loop), 3600.), 3600., 0);
@@ -1183,7 +1193,7 @@ process causing the status change.

waitpid and sys/wait.h documentation for details).

-

Example: try to exit cleanly on SIGINT and SIGTERM.

+

Example: Try to exit cleanly on SIGINT and SIGTERM.

  static void
   sigint_cb (struct ev_loop *loop, struct ev_signal *w, int revents)
   {
@@ -1316,8 +1326,8 @@ kind. There is a ev_idle_set macro, but using it is utterly pointle
 believe me.

-

Example: dynamically allocate an ev_idle, start it, and in the -callback, free it. Alos, use no error checking, as usual.

+

Example: Dynamically allocate an ev_idle watcher, start it, and in the +callback, free it. Also, use no error checking, as usual.

  static void
   idle_cb (struct ev_loop *loop, struct ev_idle *w, int revents)
   {
@@ -1552,7 +1562,7 @@ believe me.

-

OTHER FUNCTIONS

Top

+

OTHER FUNCTIONS

There are some other functions of possible interest. Described. Here. Now.

@@ -1609,7 +1619,7 @@ loop!).

-

LIBEVENT EMULATION

Top

+

LIBEVENT EMULATION

Libev offers a compatibility emulation layer for libevent. It cannot emulate the internals of libevent, so here are some usage hints:

@@ -1629,7 +1639,7 @@ to use the libev header file and library.
-

C++ SUPPORT

Top

+

C++ SUPPORT

Libev comes with some simplistic wrapper classes for C++ that mainly allow you to use some convinience methods to start/stop watchers and also change @@ -1734,7 +1744,7 @@ the constructor.

-

MACRO MAGIC

Top

+

MACRO MAGIC

Libev can be compiled with a variety of options, the most fundemantal is EV_MULTIPLICITY. This option determines wether (most) functions and @@ -1795,7 +1805,7 @@ wether multiple loops are supported or not.

-

EMBEDDING

Top

+

EMBEDDING

Libev can (and often is) directly embedded into host applications. Examples of applications that embed it include the Deliantra @@ -2099,7 +2109,7 @@ that everybody includes and which overrides some autoconf choices:

-

COMPLEXITIES

Top

+

COMPLEXITIES

In this section the complexities of (many of) the algorithms used inside libev will be explained. For complexity discussions about backends see the @@ -2122,7 +2132,7 @@ documentation for ev_default_init.

-

AUTHOR

Top

+

AUTHOR

Marc Lehmann <libev@schmorp.de>.

diff --git a/ev.pod b/ev.pod index 43db80f..1b797df 100644 --- a/ev.pod +++ b/ev.pod @@ -4,10 +4,12 @@ libev - a high performance full-featured event loop written in C =head1 SYNOPSIS - /* this is the only header you need */ #include - /* what follows is a fully working example program */ +=head1 EXAMPLE PROGRAM + + #include + ev_io stdin_watcher; ev_timer timeout_watcher; @@ -63,23 +65,28 @@ watcher. =head1 FEATURES -Libev supports select, poll, the linux-specific epoll and the bsd-specific -kqueue mechanisms for file descriptor events, relative timers, absolute -timers with customised rescheduling, signal events, process status change -events (related to SIGCHLD), and event watchers dealing with the event -loop mechanism itself (idle, prepare and check watchers). It also is quite -fast (see this L comparing -it to libevent for example). +Libev supports C