Struct otter_api_tests::crates::otter_support::imports::time::SystemTime
1.8.0 · source · [−]pub struct SystemTime(_);
Expand description
A measurement of the system clock, useful for talking to external entities like the file system or other processes.
Distinct from the Instant
type, this time measurement is not
monotonic. This means that you can save a file to the file system, then
save another file to the file system, and the second file has a
SystemTime
measurement earlier than the first. In other words, an
operation that happens after another operation in real time may have an
earlier SystemTime
!
Consequently, comparing two SystemTime
instances to learn about the
duration between them returns a Result
instead of an infallible Duration
to indicate that this sort of time drift may happen and needs to be handled.
Although a SystemTime
cannot be directly inspected, the UNIX_EPOCH
constant is provided in this module as an anchor in time to learn
information about a SystemTime
. By calculating the duration from this
fixed point in time, a SystemTime
can be converted to a human-readable time,
or perhaps some other string representation.
The size of a SystemTime
struct may vary depending on the target operating
system.
Example:
use std::time::{Duration, SystemTime};
use std::thread::sleep;
fn main() {
let now = SystemTime::now();
// we sleep for 2 seconds
sleep(Duration::new(2, 0));
match now.elapsed() {
Ok(elapsed) => {
// it prints '2'
println!("{}", elapsed.as_secs());
}
Err(e) => {
// an error occurred!
println!("Error: {e:?}");
}
}
}
Platform-specific behavior
The precision of SystemTime
can depend on the underlying OS-specific time format.
For example, on Windows the time is represented in 100 nanosecond intervals whereas Linux
can represent nanosecond intervals.
The following system calls are currently being used by now()
to find out
the current time:
Platform | System call |
---|---|
SGX | insecure_time usercall. More information on timekeeping in SGX |
UNIX | clock_gettime (Realtime Clock) |
Darwin | gettimeofday |
VXWorks | clock_gettime (Realtime Clock) |
SOLID | SOLID_RTC_ReadTime |
WASI | __wasi_clock_time_get (Realtime Clock) |
Windows | GetSystemTimePreciseAsFileTime / GetSystemTimeAsFileTime |
Disclaimer: These system calls might change over time.
Note: mathematical operations like
add
may panic if the underlying structure cannot represent the new point in time.
Implementations
sourceimpl SystemTime
impl SystemTime
1.28.0 · sourcepub const UNIX_EPOCH: SystemTime = UNIX_EPOCH
pub const UNIX_EPOCH: SystemTime = UNIX_EPOCH
An anchor in time which can be used to create new SystemTime
instances or
learn about where in time a SystemTime
lies.
This constant is defined to be “1970-01-01 00:00:00 UTC” on all systems with
respect to the system clock. Using duration_since
on an existing
SystemTime
instance can tell how far away from this point in time a
measurement lies, and using UNIX_EPOCH + duration
can be used to create a
SystemTime
instance to represent another fixed point in time.
Examples
use std::time::SystemTime;
match SystemTime::now().duration_since(SystemTime::UNIX_EPOCH) {
Ok(n) => println!("1970-01-01 00:00:00 UTC was {} seconds ago!", n.as_secs()),
Err(_) => panic!("SystemTime before UNIX EPOCH!"),
}
sourcepub fn now() -> SystemTime
pub fn now() -> SystemTime
Returns the system time corresponding to “now”.
Examples
use std::time::SystemTime;
let sys_time = SystemTime::now();
sourcepub fn duration_since(
&self,
earlier: SystemTime
) -> Result<Duration, SystemTimeError>
pub fn duration_since(
&self,
earlier: SystemTime
) -> Result<Duration, SystemTimeError>
Returns the amount of time elapsed from an earlier point in time.
This function may fail because measurements taken earlier are not
guaranteed to always be before later measurements (due to anomalies such
as the system clock being adjusted either forwards or backwards).
Instant
can be used to measure elapsed time without this risk of failure.
If successful, Ok(Duration)
is returned where the duration represents
the amount of time elapsed from the specified measurement to this one.
Returns an Err
if earlier
is later than self
, and the error
contains how far from self
the time is.
Examples
use std::time::SystemTime;
let sys_time = SystemTime::now();
let new_sys_time = SystemTime::now();
let difference = new_sys_time.duration_since(sys_time)
.expect("Clock may have gone backwards");
println!("{difference:?}");
sourcepub fn elapsed(&self) -> Result<Duration, SystemTimeError>
pub fn elapsed(&self) -> Result<Duration, SystemTimeError>
Returns the difference between the clock time when this system time was created, and the current clock time.
This function may fail as the underlying system clock is susceptible to
drift and updates (e.g., the system clock could go backwards), so this
function might not always succeed. If successful, Ok(Duration)
is
returned where the duration represents the amount of time elapsed from
this time measurement to the current time.
To measure elapsed time reliably, use Instant
instead.
Returns an Err
if self
is later than the current system time, and
the error contains how far from the current system time self
is.
Examples
use std::thread::sleep;
use std::time::{Duration, SystemTime};
let sys_time = SystemTime::now();
let one_sec = Duration::from_secs(1);
sleep(one_sec);
assert!(sys_time.elapsed().unwrap() >= one_sec);
1.34.0 · sourcepub fn checked_add(&self, duration: Duration) -> Option<SystemTime>
pub fn checked_add(&self, duration: Duration) -> Option<SystemTime>
Returns Some(t)
where t
is the time self + duration
if t
can be represented as
SystemTime
(which means it’s inside the bounds of the underlying data structure), None
otherwise.
1.34.0 · sourcepub fn checked_sub(&self, duration: Duration) -> Option<SystemTime>
pub fn checked_sub(&self, duration: Duration) -> Option<SystemTime>
Returns Some(t)
where t
is the time self - duration
if t
can be represented as
SystemTime
(which means it’s inside the bounds of the underlying data structure), None
otherwise.
Trait Implementations
sourceimpl Add<Duration> for SystemTime
impl Add<Duration> for SystemTime
sourcefn add(self, dur: Duration) -> SystemTime
fn add(self, dur: Duration) -> SystemTime
Panics
This function may panic if the resulting point in time cannot be represented by the
underlying data structure. See SystemTime::checked_add
for a version without panic.
type Output = SystemTime
type Output = SystemTime
The resulting type after applying the +
operator.
impl Add<Duration> for SystemTime
impl Add<Duration> for SystemTime
type Output = SystemTime
type Output = SystemTime
The resulting type after applying the +
operator.
fn add(self, duration: Duration) -> <SystemTime as Add<Duration>>::Output
fn add(self, duration: Duration) -> <SystemTime as Add<Duration>>::Output
Performs the +
operation. Read more
1.9.0 · sourceimpl AddAssign<Duration> for SystemTime
impl AddAssign<Duration> for SystemTime
sourcefn add_assign(&mut self, other: Duration)
fn add_assign(&mut self, other: Duration)
Performs the +=
operation. Read more
impl AddAssign<Duration> for SystemTime
impl AddAssign<Duration> for SystemTime
fn add_assign(&mut self, rhs: Duration)
fn add_assign(&mut self, rhs: Duration)
Performs the +=
operation. Read more
impl AsRef<SystemTime> for Timestamp
impl AsRef<SystemTime> for Timestamp
fn as_ref(&self) -> &SystemTime
fn as_ref(&self) -> &SystemTime
Converts this type into a shared reference of the (usually inferred) input type.
sourceimpl Clone for SystemTime
impl Clone for SystemTime
sourcefn clone(&self) -> SystemTime
fn clone(&self) -> SystemTime
Returns a copy of the value. Read more
1.0.0 · sourcefn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
Performs copy-assignment from source
. Read more
sourceimpl Debug for SystemTime
impl Debug for SystemTime
sourceimpl<'de> Deserialize<'de> for SystemTime
impl<'de> Deserialize<'de> for SystemTime
sourcefn deserialize<D>(
deserializer: D
) -> Result<SystemTime, <D as Deserializer<'de>>::Error> where
D: Deserializer<'de>,
fn deserialize<D>(
deserializer: D
) -> Result<SystemTime, <D as Deserializer<'de>>::Error> where
D: Deserializer<'de>,
Deserialize this value from the given Serde deserializer. Read more
sourceimpl<Tz> From<DateTime<Tz>> for SystemTime where
Tz: TimeZone,
impl<Tz> From<DateTime<Tz>> for SystemTime where
Tz: TimeZone,
sourcefn from(dt: DateTime<Tz>) -> SystemTime
fn from(dt: DateTime<Tz>) -> SystemTime
Converts to this type from the input type.
impl From<OffsetDateTime> for SystemTime
impl From<OffsetDateTime> for SystemTime
fn from(datetime: OffsetDateTime) -> SystemTime
fn from(datetime: OffsetDateTime) -> SystemTime
Converts to this type from the input type.
sourceimpl From<SystemTime> for DateTime<Utc>
impl From<SystemTime> for DateTime<Utc>
sourcefn from(t: SystemTime) -> DateTime<Utc>
fn from(t: SystemTime) -> DateTime<Utc>
Converts to this type from the input type.
sourceimpl From<SystemTime> for DateTime<Local>
impl From<SystemTime> for DateTime<Local>
sourcefn from(t: SystemTime) -> DateTime<Local>
fn from(t: SystemTime) -> DateTime<Local>
Converts to this type from the input type.
impl From<SystemTime> for OffsetDateTime
impl From<SystemTime> for OffsetDateTime
fn from(system_time: SystemTime) -> OffsetDateTime
fn from(system_time: SystemTime) -> OffsetDateTime
Converts to this type from the input type.
impl From<SystemTime> for FileTime
impl From<SystemTime> for FileTime
fn from(time: SystemTime) -> FileTime
fn from(time: SystemTime) -> FileTime
Converts to this type from the input type.
impl From<SystemTime> for Timestamp
impl From<SystemTime> for Timestamp
fn from(dur: SystemTime) -> Timestamp
fn from(dur: SystemTime) -> Timestamp
Converts to this type from the input type.
sourceimpl Hash for SystemTime
impl Hash for SystemTime
impl Into<SystemTime> for Timestamp
impl Into<SystemTime> for Timestamp
fn into(self) -> SystemTime
fn into(self) -> SystemTime
Converts this type into the (usually inferred) input type.
sourceimpl Ord for SystemTime
impl Ord for SystemTime
impl PartialEq<OffsetDateTime> for SystemTime
impl PartialEq<OffsetDateTime> for SystemTime
sourceimpl PartialEq<SystemTime> for SystemTime
impl PartialEq<SystemTime> for SystemTime
sourcefn eq(&self, other: &SystemTime) -> bool
fn eq(&self, other: &SystemTime) -> bool
This method tests for self
and other
values to be equal, and is used
by ==
. Read more
sourcefn ne(&self, other: &SystemTime) -> bool
fn ne(&self, other: &SystemTime) -> bool
This method tests for !=
.
impl PartialEq<SystemTime> for OffsetDateTime
impl PartialEq<SystemTime> for OffsetDateTime
impl PartialOrd<OffsetDateTime> for SystemTime
impl PartialOrd<OffsetDateTime> for SystemTime
fn partial_cmp(&self, other: &OffsetDateTime) -> Option<Ordering>
fn partial_cmp(&self, other: &OffsetDateTime) -> Option<Ordering>
This method returns an ordering between self
and other
values if one exists. Read more
1.0.0 · sourcefn lt(&self, other: &Rhs) -> bool
fn lt(&self, other: &Rhs) -> bool
This method tests less than (for self
and other
) and is used by the <
operator. Read more
1.0.0 · sourcefn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
This method tests less than or equal to (for self
and other
) and is used by the <=
operator. Read more
sourceimpl PartialOrd<SystemTime> for SystemTime
impl PartialOrd<SystemTime> for SystemTime
sourcefn partial_cmp(&self, other: &SystemTime) -> Option<Ordering>
fn partial_cmp(&self, other: &SystemTime) -> Option<Ordering>
This method returns an ordering between self
and other
values if one exists. Read more
1.0.0 · sourcefn lt(&self, other: &Rhs) -> bool
fn lt(&self, other: &Rhs) -> bool
This method tests less than (for self
and other
) and is used by the <
operator. Read more
1.0.0 · sourcefn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
This method tests less than or equal to (for self
and other
) and is used by the <=
operator. Read more
impl PartialOrd<SystemTime> for OffsetDateTime
impl PartialOrd<SystemTime> for OffsetDateTime
fn partial_cmp(&self, other: &SystemTime) -> Option<Ordering>
fn partial_cmp(&self, other: &SystemTime) -> Option<Ordering>
This method returns an ordering between self
and other
values if one exists. Read more
1.0.0 · sourcefn lt(&self, other: &Rhs) -> bool
fn lt(&self, other: &Rhs) -> bool
This method tests less than (for self
and other
) and is used by the <
operator. Read more
1.0.0 · sourcefn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
This method tests less than or equal to (for self
and other
) and is used by the <=
operator. Read more
sourceimpl Serialize for SystemTime
impl Serialize for SystemTime
sourcefn serialize<S>(
&self,
serializer: S
) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error> where
S: Serializer,
fn serialize<S>(
&self,
serializer: S
) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error> where
S: Serializer,
Serialize this value into the given Serde serializer. Read more
sourceimpl Sub<Duration> for SystemTime
impl Sub<Duration> for SystemTime
type Output = SystemTime
type Output = SystemTime
The resulting type after applying the -
operator.
sourcefn sub(self, dur: Duration) -> SystemTime
fn sub(self, dur: Duration) -> SystemTime
Performs the -
operation. Read more
impl Sub<Duration> for SystemTime
impl Sub<Duration> for SystemTime
type Output = SystemTime
type Output = SystemTime
The resulting type after applying the -
operator.
fn sub(self, duration: Duration) -> <SystemTime as Sub<Duration>>::Output
fn sub(self, duration: Duration) -> <SystemTime as Sub<Duration>>::Output
Performs the -
operation. Read more
impl Sub<OffsetDateTime> for SystemTime
impl Sub<OffsetDateTime> for SystemTime
impl Sub<SystemTime> for OffsetDateTime
impl Sub<SystemTime> for OffsetDateTime
type Output = Duration
type Output = Duration
The resulting type after applying the -
operator.
fn sub(self, rhs: SystemTime) -> <OffsetDateTime as Sub<SystemTime>>::Output
fn sub(self, rhs: SystemTime) -> <OffsetDateTime as Sub<SystemTime>>::Output
Performs the -
operation. Read more
1.9.0 · sourceimpl SubAssign<Duration> for SystemTime
impl SubAssign<Duration> for SystemTime
sourcefn sub_assign(&mut self, other: Duration)
fn sub_assign(&mut self, other: Duration)
Performs the -=
operation. Read more
impl SubAssign<Duration> for SystemTime
impl SubAssign<Duration> for SystemTime
fn sub_assign(&mut self, rhs: Duration)
fn sub_assign(&mut self, rhs: Duration)
Performs the -=
operation. Read more
impl Copy for SystemTime
impl Eq for SystemTime
impl StructuralEq for SystemTime
impl StructuralPartialEq for SystemTime
Auto Trait Implementations
impl RefUnwindSafe for SystemTime
impl Send for SystemTime
impl Sync for SystemTime
impl Unpin for SystemTime
impl UnwindSafe for SystemTime
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
impl<T> Downcast for T where
T: Any,
impl<T> Downcast for T where
T: Any,
fn into_any(self: Box<T, Global>) -> Box<dyn Any + 'static, Global>ⓘNotable traits for Box<W, Global>impl<W> Write for Box<W, Global> where
W: Write + ?Sized, impl<R> Read for Box<R, Global> where
R: Read + ?Sized, impl<F, A> Future for Box<F, A> where
F: Future + Unpin + ?Sized,
A: Allocator + 'static, type Output = <F as Future>::Output;impl<I, A> Iterator for Box<I, A> where
I: Iterator + ?Sized,
A: Allocator, type Item = <I as Iterator>::Item;
fn into_any(self: Box<T, Global>) -> Box<dyn Any + 'static, Global>ⓘNotable traits for Box<W, Global>impl<W> Write for Box<W, Global> where
W: Write + ?Sized, impl<R> Read for Box<R, Global> where
R: Read + ?Sized, impl<F, A> Future for Box<F, A> where
F: Future + Unpin + ?Sized,
A: Allocator + 'static, type Output = <F as Future>::Output;impl<I, A> Iterator for Box<I, A> where
I: Iterator + ?Sized,
A: Allocator, type Item = <I as Iterator>::Item;
W: Write + ?Sized, impl<R> Read for Box<R, Global> where
R: Read + ?Sized, impl<F, A> Future for Box<F, A> where
F: Future + Unpin + ?Sized,
A: Allocator + 'static, type Output = <F as Future>::Output;impl<I, A> Iterator for Box<I, A> where
I: Iterator + ?Sized,
A: Allocator, type Item = <I as Iterator>::Item;
Convert Box<dyn Trait>
(where Trait: Downcast
) to Box<dyn Any>
. Box<dyn Any>
can
then be further downcast
into Box<ConcreteType>
where ConcreteType
implements Trait
. Read more
fn into_any_rc(self: Rc<T>) -> Rc<dyn Any + 'static>
fn into_any_rc(self: Rc<T>) -> Rc<dyn Any + 'static>
Convert Rc<Trait>
(where Trait: Downcast
) to Rc<Any>
. Rc<Any>
can then be
further downcast
into Rc<ConcreteType>
where ConcreteType
implements Trait
. Read more
fn as_any(&self) -> &(dyn Any + 'static)
fn as_any(&self) -> &(dyn Any + 'static)
Convert &Trait
(where Trait: Downcast
) to &Any
. This is needed since Rust cannot
generate &Any
’s vtable from &Trait
’s. Read more
fn as_any_mut(&mut self) -> &mut (dyn Any + 'static)
fn as_any_mut(&mut self) -> &mut (dyn Any + 'static)
Convert &mut Trait
(where Trait: Downcast
) to &Any
. This is needed since Rust cannot
generate &mut Any
’s vtable from &mut Trait
’s. Read more
impl<A> DynCastExt for A
impl<A> DynCastExt for A
fn dyn_cast<T>(
self
) -> Result<<A as DynCastExtHelper<T>>::Target, <A as DynCastExtHelper<T>>::Source> where
A: DynCastExtHelper<T>,
T: ?Sized,
fn dyn_cast<T>(
self
) -> Result<<A as DynCastExtHelper<T>>::Target, <A as DynCastExtHelper<T>>::Source> where
A: DynCastExtHelper<T>,
T: ?Sized,
Use this to cast from one trait object type to another. Read more
fn dyn_upcast<T>(self) -> <A as DynCastExtAdvHelper<T, T>>::Target where
A: DynCastExtAdvHelper<T, T, Source = <A as DynCastExtAdvHelper<T, T>>::Target>,
T: ?Sized,
fn dyn_upcast<T>(self) -> <A as DynCastExtAdvHelper<T, T>>::Target where
A: DynCastExtAdvHelper<T, T, Source = <A as DynCastExtAdvHelper<T, T>>::Target>,
T: ?Sized,
Use this to upcast a trait to one of its supertraits. Read more
fn dyn_cast_adv<F, T>(
self
) -> Result<<A as DynCastExtAdvHelper<F, T>>::Target, <A as DynCastExtAdvHelper<F, T>>::Source> where
A: DynCastExtAdvHelper<F, T>,
F: ?Sized,
T: ?Sized,
fn dyn_cast_adv<F, T>(
self
) -> Result<<A as DynCastExtAdvHelper<F, T>>::Target, <A as DynCastExtAdvHelper<F, T>>::Source> where
A: DynCastExtAdvHelper<F, T>,
F: ?Sized,
T: ?Sized,
fn dyn_cast_with_config<C>(
self
) -> Result<<A as DynCastExtAdvHelper<<C as DynCastConfig>::Source, <C as DynCastConfig>::Target>>::Target, <A as DynCastExtAdvHelper<<C as DynCastConfig>::Source, <C as DynCastConfig>::Target>>::Source> where
C: DynCastConfig,
A: DynCastExtAdvHelper<<C as DynCastConfig>::Source, <C as DynCastConfig>::Target>,
fn dyn_cast_with_config<C>(
self
) -> Result<<A as DynCastExtAdvHelper<<C as DynCastConfig>::Source, <C as DynCastConfig>::Target>>::Target, <A as DynCastExtAdvHelper<<C as DynCastConfig>::Source, <C as DynCastConfig>::Target>>::Source> where
C: DynCastConfig,
A: DynCastExtAdvHelper<<C as DynCastConfig>::Source, <C as DynCastConfig>::Target>,
Use this to cast from one trait object type to another. With this method the type parameter is a config type that uniquely specifies which cast should be preformed. Read more
sourceimpl<Q, K> Equivalent<K> for Q where
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
impl<Q, K> Equivalent<K> for Q where
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
sourcefn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
Compare self to key
and return true
if they are equal.
sourceimpl<T> Instrument for T
impl<T> Instrument for T
sourcefn instrument(self, span: Span) -> Instrumented<Self>ⓘNotable traits for Instrumented<T>impl<T> Future for Instrumented<T> where
T: Future, type Output = <T as Future>::Output;
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sourcefn in_current_span(self) -> Instrumented<Self>ⓘNotable traits for Instrumented<T>impl<T> Future for Instrumented<T> where
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sourceimpl<T> Serialize for T where
T: Serialize + ?Sized,
impl<T> Serialize for T where
T: Serialize + ?Sized,
fn erased_serialize(&self, serializer: &mut dyn Serializer) -> Result<Ok, Error>
impl<V, T> VZip<V> for T where
V: MultiLane<T>,
impl<V, T> VZip<V> for T where
V: MultiLane<T>,
fn vzip(self) -> V
sourceimpl<T> WithSubscriber for T
impl<T> WithSubscriber for T
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S: Into<Dispatch>,
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where
S: Into<Dispatch>,
T: Future, type Output = <T as Future>::Output;
Attaches the provided Subscriber
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sourcefn with_current_subscriber(self) -> WithDispatch<Self>ⓘNotable traits for WithDispatch<T>impl<T> Future for WithDispatch<T> where
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fn with_current_subscriber(self) -> WithDispatch<Self>ⓘNotable traits for WithDispatch<T>impl<T> Future for WithDispatch<T> where
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T: Future, type Output = <T as Future>::Output;
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