core/vul/vul_timer.h File Reference

A timing facility for C++. More...

#include <vcl_iosfwd.h>

Go to the source code of this file.

Classes
class	vul_timer
	The Timer class provides timing code for performance evaluation. More...

---

Detailed Description

A timing facility for C++.

Author:

This code was originally written by Joe Rahmeh at UT Austin.

The vul_timer class provides an interface to system timing. It allows a C++ program to record the time between a reference point (mark) and now. This class uses the system time(2) interface to provide time resolution at either millisecond or microsecond granularity, depending upon operating system support and features. Since the time duration is stored in a 32-bit word, the maximum time period before rollover occurs is about 71 minutes.

Due to operating system dependencies, the accuracy of all member function results may not be as documented. For example, some operating systems do not support timers with microsecond resolution. In those cases, the values returned are provided to the nearest millisecond or other unit of time as appropriate. See the Timer header file for system specific notes.

The Timer class provides timing code for performance evaluation.

• User time: time cpu spends in user mode on behalf of the program.
• System time: time cpu spends in system mode on behalf of the program.
• Real time: what you get from a stop watch timer.

    Modifications
     Created: BMK 07/14/89  Initial design and implementation.
     Updated: LGO 09/23/89  Conform to COOL coding style.
     Updated: AFM 12/31/89  OS/2 port.
     Updated: DLS 03/22/91  New lite version.
     Updated: VDN 10/14/93  ANSI C does not have user/system time.
     Peter Vanroose   27/05/2001: Corrected the documentation
   

Definition in file vul_timer.h.