NDDSUtility Class Reference

Unsupported utility APIs. More...

Static Public Member Functions
static void	sleep (const struct DDS_Duration_t &durationIn)
	Block the calling thread for the specified duration.
static void	spin (DDS_UnsignedLongLong spinCount)
	Performs the spin operation as many times as indicated.
static DDS_UnsignedLongLong	get_spin_per_microsecond ()
	Returns the number of spin operations to perform to wait 1 microsecond.

Detailed Description

Unsupported utility APIs.

Unsupported APIs used in example code.

The static methods supplied by this class are used by the example code distributed with RTI Connext and generated by nddsgen. These methods are not supported by RTI.

Member Function Documentation

static void NDDSUtility::sleep ( const struct DDS_Duration_t &  durationIn )

static

Block the calling thread for the specified duration.

Note that the achievable resolution of sleep is OS-dependent. That is, do not assume that you can sleep for 1 nanosecond just because you can specify a 1-nanosecond sleep duration via the API. The sleep resolution on most operating systems is usually 10 ms or greater.

Parameters

durationIn

<<in>> Sleep duration.

MT Safety:

safe

Examples:

HelloWorld_publisher.cxx, and HelloWorld_subscriber.cxx.

static void NDDSUtility::spin ( DDS_UnsignedLongLong  spinCount )

static

Performs the spin operation as many times as indicated.

Spinning is the action of performing useless operations in a for loop in order to actively wait some time without yielding the CPU. Given that the resolution of sleep is in the order of ms, you can use this utility to wait times in the order of microseconds. To properly use this functionality, it is useful to measure previously the number of spin operations needed to wait the equivalent to 1 microsecond (using the utility get_spin_per_microsecond) and then compute the corresponding spin count desired.

Parameters

spinCount

<<in>> Number of spin operations to perform.

static DDS_UnsignedLongLong NDDSUtility::get_spin_per_microsecond ( )

static

Returns the number of spin operations to perform to wait 1 microsecond.

This utility can be used to measure how many spin operations must be performed to wait 1 microsecond. Since the time that it takes the CPU to perform 1 spin operation depends on the CPU frequency, it is recommended to use this utility before using spin().

Returns

Number of spin operations to wait 1 microsecond.