| … | |
… | |
| 1991 | delay has actually elapsed, or in other words, it always errs on the "too |
1991 | delay has actually elapsed, or in other words, it always errs on the "too |
| 1992 | late" side of things. |
1992 | late" side of things. |
| 1993 | |
1993 | |
| 1994 | =head3 The special problem of time updates |
1994 | =head3 The special problem of time updates |
| 1995 | |
1995 | |
| 1996 | Establishing the current time is a costly operation (it usually takes at |
1996 | Establishing the current time is a costly operation (it usually takes |
| 1997 | least two system calls): EV therefore updates its idea of the current |
1997 | at least one system call): EV therefore updates its idea of the current |
| 1998 | time only before and after C<ev_run> collects new events, which causes a |
1998 | time only before and after C<ev_run> collects new events, which causes a |
| 1999 | growing difference between C<ev_now ()> and C<ev_time ()> when handling |
1999 | growing difference between C<ev_now ()> and C<ev_time ()> when handling |
| 2000 | lots of events in one iteration. |
2000 | lots of events in one iteration. |
| 2001 | |
2001 | |
| 2002 | The relative timeouts are calculated relative to the C<ev_now ()> |
2002 | The relative timeouts are calculated relative to the C<ev_now ()> |
| … | |
… | |
| 2009 | |
2009 | |
| 2010 | If the event loop is suspended for a long time, you can also force an |
2010 | If the event loop is suspended for a long time, you can also force an |
| 2011 | update of the time returned by C<ev_now ()> by calling C<ev_now_update |
2011 | update of the time returned by C<ev_now ()> by calling C<ev_now_update |
| 2012 | ()>. |
2012 | ()>. |
| 2013 | |
2013 | |
| 2014 | =head3 The special problem of unsychronised clocks |
2014 | =head3 The special problem of unsynchronised clocks |
| 2015 | |
2015 | |
| 2016 | Modern systems have a variety of clocks - libev itself uses the normal |
2016 | Modern systems have a variety of clocks - libev itself uses the normal |
| 2017 | "wall clock" clock and, if available, the monotonic clock (to avoid time |
2017 | "wall clock" clock and, if available, the monotonic clock (to avoid time |
| 2018 | jumps). |
2018 | jumps). |
| 2019 | |
2019 | |
