sd_event_now
systemd
Developer
Lennart
Poettering
lennart@poettering.net
sd_event_now
3
sd_event_now
Retrieve current event loop iteration timestamp
#include <systemd/sd-event.h>
int sd_event_now
sd_event *event
clockid_t clock
uint64_t *usec
Description
sd_event_now() returns the time when
the most recent event loop iteration began. A timestamp
is taken right after returning from the event sleep, and before
dispatching any event sources. The event
parameter specifies the event loop object to retrieve the timestamp
from. The clock parameter specifies the clock to
retrieve the timestamp for, and is one of
CLOCK_REALTIME (or equivalently
CLOCK_REALTIME_ALARM),
CLOCK_MONOTONIC, or
CLOCK_BOOTTIME (or equivalently
CLOCK_BOOTTIME_ALARM), see
clock_gettime2
for more information on the various clocks. The retrieved
timestamp is stored in the usec parameter,
in µs since the clock's epoch. If this function is invoked before
the first event loop iteration, the current time is returned, as
reported by clock_gettime(). To distinguish
this case from a regular invocation the return value will be
positive, and zero when the returned timestamp refers to an actual
event loop iteration.
Return Value
If the first event loop iteration has not run yet
sd_event_now() writes current time to
usec and returns a positive return value.
Otherwise, it will write the requested timestamp to usec
and return 0. On failure, the call returns a negative errno-style
error code.
Errors
Returned values may indicate the following problems:
-EINVAL
An invalid parameter was
passed.
-ECHILD
The event loop object was created in a
different process.
See Also
systemd1,
sd-event3,
sd_event_new3,
sd_event_add_time3,
clock_gettime2