RTI Connext C API
Version 7.0.0
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Other Utilities, such as NDDS_Utility_spin. More...
Functions | |
void | NDDS_Utility_sleep (const struct DDS_Duration_t *durationIn) |
Block the calling thread for the specified duration. More... | |
void | NDDS_Utility_spin (DDS_UnsignedLongLong spinCount) |
Performs the spin operation as many times as indicated. More... | |
DDS_UnsignedLongLong | NDDS_Utility_get_spin_per_microsecond (void) |
Returns the number of spin operations to perform to wait 1 microsecond. More... | |
Other Utilities, such as NDDS_Utility_spin.
void NDDS_Utility_sleep | ( | const struct DDS_Duration_t * | durationIn | ) |
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.
durationIn | <<in>> Sleep duration. Cannot be NULL. |
void NDDS_Utility_spin | ( | DDS_UnsignedLongLong | spinCount | ) |
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 microsecond (using the utility get_spin_per_microsecond) and then compute the corresponding spin count desired.
spinCount | <<in>> Number of spin operations to perform. |
DDS_UnsignedLongLong NDDS_Utility_get_spin_per_microsecond | ( | void | ) |
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().