#[repr(transparent)]pub struct Timer(_);
time
only.Expand description
A Unix signal per-process timer.
Implementations
sourceimpl Timer
impl Timer
sourcepub fn new(clockid: ClockId, sigevent: SigEvent) -> Result<Self>
pub fn new(clockid: ClockId, sigevent: SigEvent) -> Result<Self>
Creates a new timer based on the clock defined by clockid
. The details
of the signal and its handler are defined by the passed sigevent
.
sourcepub fn set(
&mut self,
expiration: Expiration,
flags: TimerSetTimeFlags
) -> Result<()>
pub fn set(
&mut self,
expiration: Expiration,
flags: TimerSetTimeFlags
) -> Result<()>
Set a new alarm on the timer.
Types of alarm
There are 3 types of alarms you can set:
-
one shot: the alarm will trigger once after the specified amount of time. Example: I want an alarm to go off in 60s and then disable itself.
-
interval: the alarm will trigger every specified interval of time. Example: I want an alarm to go off every 60s. The alarm will first go off 60s after I set it and every 60s after that. The alarm will not disable itself.
-
interval delayed: the alarm will trigger after a certain amount of time and then trigger at a specified interval. Example: I want an alarm to go off every 60s but only start in 1h. The alarm will first trigger 1h after I set it and then every 60s after that. The alarm will not disable itself.
Relative vs absolute alarm
If you do not set any TimerSetTimeFlags
, then the TimeSpec
you pass
to the Expiration
you want is relative. If however you want an alarm
to go off at a certain point in time, you can set TFD_TIMER_ABSTIME
.
Then the one shot TimeSpec and the delay TimeSpec of the delayed
interval are going to be interpreted as absolute.
Disabling alarms
Note: Only one alarm can be set for any given timer. Setting a new alarm actually removes the previous one.
Note: Setting a one shot alarm with a 0s TimeSpec disable the alarm altogether.
sourcepub fn get(&self) -> Result<Option<Expiration>>
pub fn get(&self) -> Result<Option<Expiration>>
Get the parameters for the alarm currently set, if any.
sourcepub fn overruns(&self) -> i32
pub fn overruns(&self) -> i32
Return the number of timers that have overrun
Each timer is able to queue one signal to the process at a time, meaning
if the signal is not handled before the next expiration the timer has
‘overrun’. This function returns how many times that has happened to
this timer, up to libc::DELAYTIMER_MAX
. If more than the maximum
number of overruns have happened the return is capped to the maximum.
Trait Implementations
Auto Trait Implementations
impl RefUnwindSafe for Timer
impl !Send for Timer
impl !Sync for Timer
impl Unpin for Timer
impl UnwindSafe for Timer
Blanket Implementations
sourceimpl<T> BorrowMut<T> for T where
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more