System.Clock.Seconds

Documentation

data Clock

Clock types. A clock may be system-wide (that is, visible to all processes) or per-process (measuring time that is meaningful only within a process). All implementations shall support Realtime.

Constructors

Monotonic

The identifier for the system-wide monotonic clock, which is defined as a clock measuring real time, whose value cannot be set via clock_settime and which cannot have negative clock jumps. The maximum possible clock jump shall be implementation defined. For this clock, the value returned by getTime represents the amount of time (in seconds and nanoseconds) since an unspecified point in the past (for example, system start-up time, or the Epoch). This point does not change after system start-up time. Note that the absolute value of the monotonic clock is meaningless (because its origin is arbitrary), and thus there is no need to set it. Furthermore, realtime applications can rely on the fact that the value of this clock is never set. (Identical to Boottime since Linux 4.17, see https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d6ed449afdb38f89a7b38ec50e367559e1b8f71f) CLOCK_MONOTONIC (macOS - SYSTEM_CLOCK)

Realtime

The identifier of the system-wide clock measuring real time. For this clock, the value returned by getTime represents the amount of time (in seconds and nanoseconds) since the Epoch. CLOCK_REALTIME (macOS - CALENDAR_CLOCK, Windows - GetSystemTimeAsFileTime)

ProcessCPUTime

The identifier of the CPU-time clock associated with the calling process. For this clock, the value returned by getTime represents the amount of execution time of the current process.

ThreadCPUTime

The identifier of the CPU-time clock associated with the calling OS thread. For this clock, the value returned by getTime represents the amount of execution time of the current OS thread.

MonotonicRaw

(since Linux 2.6.28, macOS 10.12) Similar to Monotonic, but provides access to a raw hardware-based time that is not subject to NTP adjustments or the incremental adjustments performed by adjtime(3). CLOCK_MONOTONIC_RAW (Windows - QueryPerformanceCounter, QueryPerformanceFrequency)

Boottime

(since Linux 2.6.39; Linux-specific) Identical to Monotonic, except it also includes any time that the system is suspended. This allows applications to get a suspend-aware monotonic clock without having to deal with the complications of Realtime, which may have discontinuities if the time is changed using settimeofday(2). (since Linux 4.17; identical to Monotonic) CLOCK_BOOTTIME

MonotonicCoarse

(since Linux 2.6.32; Linux-specific) A faster but less precise version of Monotonic. Use when you need very fast, but not fine-grained timestamps. CLOCK_MONOTONIC_COARSE

RealtimeCoarse

(since Linux 2.6.32; Linux-specific) A faster but less precise version of Realtime. Use when you need very fast, but not fine-grained timestamps. CLOCK_REALTIME_COARSE

Instances

Enum Clock

Defined in System.Clock

Methods

succ :: Clock -> Clock

pred :: Clock -> Clock

toEnum :: Int -> Clock

fromEnum :: Clock -> Int

enumFrom :: Clock -> [Clock]

enumFromThen :: Clock -> Clock -> [Clock]

enumFromTo :: Clock -> Clock -> [Clock]

enumFromThenTo :: Clock -> Clock -> Clock -> [Clock]

Generic Clock

Defined in System.Clock

Associated Types

type Rep Clock :: Type -> Type

Methods

from :: Clock -> Rep Clock x

to :: Rep Clock x -> Clock

Read Clock

Defined in System.Clock

Methods

readsPrec :: Int -> ReadS Clock

readList :: ReadS [Clock]

readPrec :: ReadPrec Clock

readListPrec :: ReadPrec [Clock]

Show Clock

Defined in System.Clock

Methods

showsPrec :: Int -> Clock -> ShowS

show :: Clock -> String

showList :: [Clock] -> ShowS

Eq Clock

Defined in System.Clock

Methods

(==) :: Clock -> Clock -> Bool

(/=) :: Clock -> Clock -> Bool

type Rep Clock

Defined in System.Clock

type Rep Clock = D1 ('MetaData "Clock" "System.Clock" "clock-0.8.4-Jy4Kv9S0UB92EJF23fZVmY" 'False) (((C1 ('MetaCons "Monotonic" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Realtime" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "ProcessCPUTime" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "ThreadCPUTime" 'PrefixI 'False) (U1 :: Type -> Type))) :+: ((C1 ('MetaCons "MonotonicRaw" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Boottime" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "MonotonicCoarse" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "RealtimeCoarse" 'PrefixI 'False) (U1 :: Type -> Type))))

newtype Seconds

Constructors

Seconds

Fields

• toTimeSpec :: TimeSpec

Instances

Storable Seconds

Defined in System.Clock.Seconds

Methods

sizeOf :: Seconds -> Int

alignment :: Seconds -> Int

peekElemOff :: Ptr Seconds -> Int -> IO Seconds

pokeElemOff :: Ptr Seconds -> Int -> Seconds -> IO ()

peekByteOff :: Ptr b -> Int -> IO Seconds

pokeByteOff :: Ptr b -> Int -> Seconds -> IO ()

peek :: Ptr Seconds -> IO Seconds

poke :: Ptr Seconds -> Seconds -> IO ()

Bounded Seconds

Defined in System.Clock.Seconds

Methods

minBound :: Seconds

maxBound :: Seconds

Enum Seconds

Defined in System.Clock.Seconds

Methods

succ :: Seconds -> Seconds

pred :: Seconds -> Seconds

toEnum :: Int -> Seconds

fromEnum :: Seconds -> Int

enumFrom :: Seconds -> [Seconds]

enumFromThen :: Seconds -> Seconds -> [Seconds]

enumFromTo :: Seconds -> Seconds -> [Seconds]

enumFromThenTo :: Seconds -> Seconds -> Seconds -> [Seconds]

Generic Seconds

Defined in System.Clock.Seconds

Associated Types

type Rep Seconds :: Type -> Type

Methods

from :: Seconds -> Rep Seconds x

to :: Rep Seconds x -> Seconds

Num Seconds

Defined in System.Clock.Seconds

Methods

(+) :: Seconds -> Seconds -> Seconds

(-) :: Seconds -> Seconds -> Seconds

(*) :: Seconds -> Seconds -> Seconds

negate :: Seconds -> Seconds

abs :: Seconds -> Seconds

signum :: Seconds -> Seconds

fromInteger :: Integer -> Seconds

Read Seconds

Defined in System.Clock.Seconds

Methods

readsPrec :: Int -> ReadS Seconds

readList :: ReadS [Seconds]

readPrec :: ReadPrec Seconds

readListPrec :: ReadPrec [Seconds]

Fractional Seconds

Defined in System.Clock.Seconds

Methods

(/) :: Seconds -> Seconds -> Seconds

recip :: Seconds -> Seconds

fromRational :: Rational -> Seconds

Real Seconds

Defined in System.Clock.Seconds

Methods

toRational :: Seconds -> Rational

RealFrac Seconds

Defined in System.Clock.Seconds

Methods

properFraction :: Integral b => Seconds -> (b, Seconds)

truncate :: Integral b => Seconds -> b

round :: Integral b => Seconds -> b

ceiling :: Integral b => Seconds -> b

floor :: Integral b => Seconds -> b

Show Seconds

Defined in System.Clock.Seconds

Methods

showsPrec :: Int -> Seconds -> ShowS

show :: Seconds -> String

showList :: [Seconds] -> ShowS

Eq Seconds

Defined in System.Clock.Seconds

Methods

(==) :: Seconds -> Seconds -> Bool

(/=) :: Seconds -> Seconds -> Bool

Ord Seconds

Defined in System.Clock.Seconds

Methods

compare :: Seconds -> Seconds -> Ordering

(<) :: Seconds -> Seconds -> Bool

(<=) :: Seconds -> Seconds -> Bool

(>) :: Seconds -> Seconds -> Bool

(>=) :: Seconds -> Seconds -> Bool

max :: Seconds -> Seconds -> Seconds

min :: Seconds -> Seconds -> Seconds

type Rep Seconds

Defined in System.Clock.Seconds

type Rep Seconds = D1 ('MetaData "Seconds" "System.Clock.Seconds" "clock-0.8.4-Jy4Kv9S0UB92EJF23fZVmY" 'True) (C1 ('MetaCons "Seconds" 'PrefixI 'True) (S1 ('MetaSel ('Just "toTimeSpec") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 TimeSpec)))

getTime :: Clock -> IO Seconds

The getTime function shall return the current value for the specified clock.

getRes :: Clock -> IO Seconds

The getRes function shall return the resolution of any clock. Clock resolutions are implementation-defined and cannot be set by a process.

fromNanoSecs :: Integer -> Seconds

Seconds from nano seconds.

toNanoSecs :: Seconds -> Integer

Seconds to nano seconds.

diffTimeSpec :: Seconds -> Seconds -> Seconds

Compute the absolute difference.