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Comparing libev/ev.pod (file contents):
Revision 1.457 by root, Fri Sep 6 22:17:52 2019 UTC vs.
Revision 1.459 by root, Wed Jan 22 01:50:42 2020 UTC

… …
480unblocking the signals. 480unblocking the signals.
481 481
482It's also required by POSIX in a threaded program, as libev calls 482It's also required by POSIX in a threaded program, as libev calls
483C<sigprocmask>, whose behaviour is officially unspecified. 483C<sigprocmask>, whose behaviour is officially unspecified.
484 484
485This flag's behaviour will become the default in future versions of libev. 485=item C<EVFLAG_NOTIMERFD>
486
487When this flag is specified, the libev will avoid using a C<timerfd> to
488detect time jumps. It will still be able to detect time jumps, but takes
489longer and has a lower accuracy in doing so, but saves a file descriptor
490per loop.
491
492The current implementation only tries to use a C<timerfd> when the first
493C<ev_periodic> watcher is started and falls back on other methods if it
494cannot be created, but this behaviour might change in the future.
486 495
487=item C<EVBACKEND_SELECT> (value 1, portable select backend) 496=item C<EVBACKEND_SELECT> (value 1, portable select backend)
488 497
489This is your standard select(2) backend. Not I<completely> standard, as 498This is your standard select(2) backend. Not I<completely> standard, as
490libev tries to roll its own fd_set with no limits on the number of fds, 499libev tries to roll its own fd_set with no limits on the number of fds,
… …
1639 1648
1640This section describes each watcher in detail, but will not repeat 1649This section describes each watcher in detail, but will not repeat
1641information given in the last section. Any initialisation/set macros, 1650information given in the last section. Any initialisation/set macros,
1642functions and members specific to the watcher type are explained. 1651functions and members specific to the watcher type are explained.
1643 1652
1644Members are additionally marked with either I<[read-only]>, meaning that, 1653Most members are additionally marked with either I<[read-only]>, meaning
1645while the watcher is active, you can look at the member and expect some 1654that, while the watcher is active, you can look at the member and expect
1646sensible content, but you must not modify it (you can modify it while the 1655some sensible content, but you must not modify it (you can modify it while
1647watcher is stopped to your hearts content), or I<[read-write]>, which 1656the watcher is stopped to your hearts content), or I<[read-write]>, which
1648means you can expect it to have some sensible content while the watcher 1657means you can expect it to have some sensible content while the watcher
1649is active, but you can also modify it. Modifying it may not do something 1658is active, but you can also modify it. Modifying it may not do something
1650sensible or take immediate effect (or do anything at all), but libev will 1659sensible or take immediate effect (or do anything at all), but libev will
1651not crash or malfunction in any way. 1660not crash or malfunction in any way.
1652 1661
1662In any case, the documentation for each member will explain what the
1663effects are, and if there are any additional access restrictions.
1653 1664
1654=head2 C<ev_io> - is this file descriptor readable or writable? 1665=head2 C<ev_io> - is this file descriptor readable or writable?
1655 1666
1656I/O watchers check whether a file descriptor is readable or writable 1667I/O watchers check whether a file descriptor is readable or writable
1657in each iteration of the event loop, or, more precisely, when reading 1668in each iteration of the event loop, or, more precisely, when reading
… …
1820 1831
1821Configures an C<ev_io> watcher. The C<fd> is the file descriptor to 1832Configures an C<ev_io> watcher. The C<fd> is the file descriptor to
1822receive events for and C<events> is either C<EV_READ>, C<EV_WRITE> or 1833receive events for and C<events> is either C<EV_READ>, C<EV_WRITE> or
1823C<EV_READ | EV_WRITE>, to express the desire to receive the given events. 1834C<EV_READ | EV_WRITE>, to express the desire to receive the given events.
1824 1835
1825=item int fd [read-only] 1836=item ev_io_modify (ev_io *, int events)
1826 1837
1827The file descriptor being watched. 1838Similar to C<ev_io_set>, but only changes the event mask. Using this might
1839be faster with some backends, as libev can assume that the C<fd> still
1840refers to the same underlying file description, something it cannot do
1841when using C<ev_io_set>.
1828 1842
1843=item int fd [no-modify]
1844
1845The file descriptor being watched. While it can be read at any time, you
1846must not modify this member even when the watcher is stopped - always use
1847C<ev_io_set> for that.
1848
1829=item int events [read-only] 1849=item int events [no-modify]
1830 1850
1831The events being watched. 1851The set of events being watched, among other flags. This field is a
1852bit set - to test for C<EV_READ>, use C<< w->events & EV_READ >>, and
1853similarly for C<EV_WRITE>.
1854
1855As with C<fd>, you must not modify this member even when the watcher is
1856stopped, always use C<ev_io_set> or C<ev_io_modify> for that.
1832 1857
1833=back 1858=back
1834 1859
1835=head3 Examples 1860=head3 Examples
1836 1861
… …
4615available and will probe for kernel support at runtime. This will improve 4640available and will probe for kernel support at runtime. This will improve
4616C<ev_signal> and C<ev_async> performance and reduce resource consumption. 4641C<ev_signal> and C<ev_async> performance and reduce resource consumption.
4617If undefined, it will be enabled if the headers indicate GNU/Linux + Glibc 4642If undefined, it will be enabled if the headers indicate GNU/Linux + Glibc
46182.7 or newer, otherwise disabled. 46432.7 or newer, otherwise disabled.
4619 4644
4645=item EV_USE_SIGNALFD
4646
4647If defined to be C<1>, then libev will assume that C<signalfd ()> is
4648available and will probe for kernel support at runtime. This enables
4649the use of EVFLAG_SIGNALFD for faster and simpler signal handling. If
4650undefined, it will be enabled if the headers indicate GNU/Linux + Glibc
46512.7 or newer, otherwise disabled.
4652
4653=item EV_USE_TIMERFD
4654
4655If defined to be C<1>, then libev will assume that C<timerfd ()> is
4656available and will probe for kernel support at runtime. This allows
4657libev to detect time jumps accurately. If undefined, it will be enabled
4658if the headers indicate GNU/Linux + Glibc 2.8 or newer and define
4659C<TFD_TIMER_CANCEL_ON_SET>, otherwise disabled.
4660
4661=item EV_USE_EVENTFD
4662
4663If defined to be C<1>, then libev will assume that C<eventfd ()> is
4664available and will probe for kernel support at runtime. This will improve
4665C<ev_signal> and C<ev_async> performance and reduce resource consumption.
4666If undefined, it will be enabled if the headers indicate GNU/Linux + Glibc
46672.7 or newer, otherwise disabled.
4668
4620=item EV_USE_SELECT 4669=item EV_USE_SELECT
4621 4670
4622If undefined or defined to be C<1>, libev will compile in support for the 4671If undefined or defined to be C<1>, libev will compile in support for the
4623C<select>(2) backend. No attempt at auto-detection will be done: if no 4672C<select>(2) backend. No attempt at auto-detection will be done: if no
4624other method takes over, select will be it. Otherwise the select backend 4673other method takes over, select will be it. Otherwise the select backend

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