bsls_systemclocktype

Detailed Description

Outline

• Purpose
• Classes
• Description
  • Enumerators
  • Usage
    • Example 1: Basic Syntax

Purpose

Enumerate the set of system clock types.

Classes

• bsls::SystemClockType: namespace for a clock type enum

Description

This component provides a namespace for the enum type bsls::SystemClockType::Enum, which enumerates the set of system clock types. A bsls::SystemClockType is particularly important when providing time-out values to synchronization methods where those time-outs must be consistent in environments where the system clocks may be changed.

Enumerators

Name          Description
-----------   -------------------------------------------------------------
e_REALTIME    System clock that returns the current wall time maintained by
              the system, and which is affected by adjustments to the
              system's clock (i.e., time values returned may jump
              "forwards" and "backwards" as the current time-of-day is
              changed on the system).
 
e_MONOTONIC   System clock that returns the elapsed time since some
              unspecified starting point in the past.  The returned values
              are monotonically non-decreasing, and are generally not
              affected by changes to the system time.

Usage

This section illustrates intended use of this component.

Example 1: Basic Syntax

The following snippets of code provide a simple illustration of using bsls::SystemClockType.

First, we create a variable value of type bsls::SystemClockType::Enum and initialize it with the enumerator value bsls::SystemClockType::e_MONOTONIC:

bsls::SystemClockType::Enum value = bsls::SystemClockType::e_MONOTONIC;

Now, we store the address of its ASCII representation in a pointer variable, asciiValue, of type const char *:

const char *asciiValue = bsls::SystemClockType::toAscii(value);

Finally, we verify the value of asciiValue:

assert(0 == strcmp(asciiValue, "MONOTONIC"));