Safe Haskell	Safe-Inferred
Language	Haskell98

System.Clock

Description

High-resolution, realtime clock and timer functions for Posix

Synopsis

Documentation

data Clock Source

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 CLOCK_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.
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.
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.

Instances

Enum Clock
Eq Clock
Read Clock
Show Clock
Generic Clock
Typeable * Clock
type Rep Clock

data TimeSpec Source

TimeSpec structure

Constructors

TimeSpec
Fields sec :: !Int64 seconds nsec :: !Int64 nanoseconds

Instances

Eq TimeSpec
Num TimeSpec
Ord TimeSpec
Read TimeSpec
Show TimeSpec
Generic TimeSpec
Storable TimeSpec
Typeable * TimeSpec
type Rep TimeSpec

getTime :: Clock -> IO TimeSpec Source

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

getRes :: Clock -> IO TimeSpec Source

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

diffTimeSpec :: TimeSpec -> TimeSpec -> TimeSpec Source

Compute the absolute difference.