boost::attributes::timer Class Reference

A class of an attribute that makes an attribute value of the time interval since construction. More...

#include <timer.hpp>

Inheritance diagram for boost::attributes::timer:

Collaboration diagram for boost::attributes::timer:

Public Types
typedef utc_time_traits::time_type::time_duration_type	value_type
	Attribute value type. More...

Public Member Functions
	timer ()
	Constructor. More...
	timer (cast_source const &source)
	Constructor for casting support. More...
bool	operator! () const BOOST_NOEXCEPT
	Verifies that the factory is not in empty state. More...
attribute_value	get_value () const
void	swap (attribute &that) BOOST_NOEXCEPT
	The method swaps two factories (i.e. More...

Protected Member Functions
impl *	get_impl () const BOOST_NOEXCEPT
void	set_impl (intrusive_ptr< impl > p) BOOST_NOEXCEPT
	Sets the pointer to the factory implementation. More...

Detailed Description

A class of an attribute that makes an attribute value of the time interval since construction.

The timer attribute calculates the time passed since its construction and returns it on value acquisition. The attribute value type is boost::posix_time::time_duration.

On Windows platform there are two implementations of the attribute. The default one is more precise but a bit slower. This version uses QueryPerformanceFrequence/QueryPerformanceCounter API to calculate elapsed time.

There are known problems with these functions when used with some CPUs, notably AMD Athlon with Cool'n'Quiet technology enabled. See the following links for more information and possible resolutions:

http://support.microsoft.com/?scid=kb;en-us;895980 http://support.microsoft.com/?id=896256

In case if none of these solutions apply, you are free to define BOOST_LOG_NO_QUERY_PERFORMANCE_COUNTER macro to fall back to another implementation based on Boost.DateTime.

Member Typedef Documentation

typedef utc_time_traits::time_type::time_duration_type boost::attributes::timer::value_type

Attribute value type.

Constructor & Destructor Documentation

boost::attributes::timer::timer

(

)

Constructor.

Starts time counting.

boost::attributes::timer::timer ( cast_source const &  source )

explicit

Constructor for casting support.

Member Function Documentation

impl* boost::attribute::get_impl ( ) const

inlineprotectedinherited

Returns

The pointer to the implementation

References boost::intrusive_ptr< T >::get().

Referenced by boost::attribute_cast(), boost::attributes::constant< process_id >::get(), boost::attributes::mutable_constant< channel_type >::get_impl(), and boost::attributes::mutable_constant< T, void, void, void >::get_impl().

attribute_value boost::attribute::get_value ( ) const

inherited

Returns

The actual attribute value. It shall not return empty values (exceptions shall be used to indicate errors).

bool boost::attribute::operator! ( ) const

inlineinherited

Verifies that the factory is not in empty state.

Verifies that the factory is in empty state

void boost::attribute::set_impl ( intrusive_ptr< impl >  p )

inlineprotectedinherited

Sets the pointer to the factory implementation.

Parameters

p	Pointer to the implementation. Must not be NULL.

References boost::multiprecision::backends::p, and boost::intrusive_ptr< T >::swap().

Referenced by boost::attributes::counter< T >::counter().

void boost::attribute::swap ( attribute &  that )

inlineinherited

The method swaps two factories (i.e.

their implementations).

References boost::intrusive_ptr< T >::swap().

Referenced by boost::sources::aux::severity_level< severity_level >::operator=(), and boost::sources::basic_severity_logger< BaseT, LevelT >::swap_unlocked().

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The documentation for this class was generated from the following file:

• boost_1_57_0/boost/log/attributes/timer.hpp