GetThreadTimes The GetThreadTimes function retrieves timing information for the specified thread.BOOL GetThreadTimes( HANDLE hThread, // handle to thread LPFILETIME lpCreationTime, // thread creation time LPFILETIME lpExitTime, // thread exit time LPFILETIME lpKernelTime, // thread kernel-mode time LPFILETIME lpUserTime // thread user-mode time ); Parameters hThread [in] Handle to the thread whose timing information is sought. This handle must have the THREAD_QUERY_INFORMATION access right. For more information, see Thread Security and Access Rights. lpCreationTime [out] Pointer to a FILETIME structure that receives the creation time of the thread. lpExitTime [out] Pointer to a FILETIME structure that receives the exit time of the thread. If the thread has not exited, the content of this structure is undefined. lpKernelTime [out] Pointer to a FILETIME structure that receives the amount of time that the thread has executed in kernel mode. lpUserTime [out] Pointer to a FILETIME structure that receives the amount of time that the thread has executed in user mode. Return Values If the function succeeds, the return value is nonzero.If the function fails, the return value is zero. To get extended error information, call GetLastError. Res All times are expressed using FILETIME data structures. Such a structure contains two 32-bit values that combine to form a 64-bit count of 100-nanosecond time units. Thread creation and exit times are points in time expressed as the amount of time that has elapsed since midnight on January 1, 1601 at Greenwich, England. There are several functions that an application can use to convert such values to more generally useful forms; see Time Functions. Thread kernel mode and user mode times are amounts of time. For example, if a thread has spent one second in kernel mode, this function will fill the FILETIME structure specified by lpKernelTime with a 64-bit value of ten million. That is the number of 100-nanosecond units in one second. Requirements Windows NT/2000/XP: Included in Windows NT 3.5 and later. Windows 95/98/Me: Unsupported. Header: Declared in Winbase.h; include Windows.h. Library: Use Kernel32.lib.GetProcessTimes The GetProcessTimes function retrieves timing information for the specified process. BOOL GetProcessTimes( HANDLE hProcess, // handle to process LPFILETIME lpCreationTime, // process creation time LPFILETIME lpExitTime, // process exit time LPFILETIME lpKernelTime, // process kernel-mode time LPFILETIME lpUserTime // process user-mode time ); Parameters hProcess [in] Handle to the process whose timing information is sought. This handle must be created with the PROCESS_QUERY_INFORMATION access right. For more information, see Process Security and Access Rights. lpCreationTime [out] Pointer to a FILETIME structure that receives the creation time of the process. lpExitTime [out] Pointer to a FILETIME structure that receives the exit time of the process. If the process has not exited, the content of this structure is undefined. lpKernelTime [out] Pointer to a FILETIME structure that receives the amount of time that the process has executed in kernel mode. The time that each of the threads of the process has executed in kernel mode is determined, and then all of those times are summed together to obtain this value. lpUserTime [out] Pointer to a FILETIME structure that receives the amount of time that the process has executed in user mode. The time that each of the threads of the process has executed in user mode is determined, and then all of those times are summed together to obtain this value. Return Values If the function succeeds, the return value is nonzero.If the function fails, the return value is zero. To get extended error information, call GetLastError. Res All times are expressed using FILETIME data structures. Such a structure contains two 32-bit values that combine to form a 64-bit count of 100-nanosecond time units. Process creation and exit times are points in time expressed as the amount of time that has elapsed since midnight on January 1, 1601 at Greenwich, England. There are several functions that an application can use to convert such values to more generally useful forms. Process kernel mode and user mode times are amounts of time. For example, if a process has spent one second in kernel mode, this function will fill the FILETIME structure specified by lpKernelTime with a 64-bit value of ten million. That is the number of 100-nanosecond units in one second. Requirements Windows NT/2000/XP: Included in Windows NT 3.5 and later. Windows 95/98/Me: Unsupported. Header: Declared in Winbase.h; include Windows.h. Library: Use Kernel32.lib.
GetTickCount()在多线程环境下是不准确的
能说清楚吗第一次用GetTickCount()和第二次用GetTickCount()的目的是什么?
//at the beginning, get start time __int64 lfreq; BOOL bret=QueryPerformanceFrequency((LARGE_INTEGER*)&lfreq); __int64 lstart; QueryPerformanceCounter((LARGE_INTEGER*)&lstart); ...... //at the end, get the end time __int64 lstop; QueryPerformanceCounter((LARGE_INTEGER*)&lstop);__int64 lruntime=lstop - lstart; double dsec= lruntime/lfreq;
那从程序开始时调用一下,中间再调用一下不就可以知道程序运行时间了吗?
The GetThreadTimes function retrieves timing information for the specified thread.BOOL GetThreadTimes(
HANDLE hThread, // handle to thread
LPFILETIME lpCreationTime, // thread creation time
LPFILETIME lpExitTime, // thread exit time
LPFILETIME lpKernelTime, // thread kernel-mode time
LPFILETIME lpUserTime // thread user-mode time
);
Parameters
hThread
[in] Handle to the thread whose timing information is sought. This handle must have the THREAD_QUERY_INFORMATION access right. For more information, see Thread Security and Access Rights.
lpCreationTime
[out] Pointer to a FILETIME structure that receives the creation time of the thread.
lpExitTime
[out] Pointer to a FILETIME structure that receives the exit time of the thread. If the thread has not exited, the content of this structure is undefined.
lpKernelTime
[out] Pointer to a FILETIME structure that receives the amount of time that the thread has executed in kernel mode.
lpUserTime
[out] Pointer to a FILETIME structure that receives the amount of time that the thread has executed in user mode.
Return Values
If the function succeeds, the return value is nonzero.If the function fails, the return value is zero. To get extended error information, call GetLastError. Res
All times are expressed using FILETIME data structures. Such a structure contains two 32-bit values that combine to form a 64-bit count of 100-nanosecond time units. Thread creation and exit times are points in time expressed as the amount of time that has elapsed since midnight on January 1, 1601 at Greenwich, England. There are several functions that an application can use to convert such values to more generally useful forms; see Time Functions. Thread kernel mode and user mode times are amounts of time. For example, if a thread has spent one second in kernel mode, this function will fill the FILETIME structure specified by lpKernelTime with a 64-bit value of ten million. That is the number of 100-nanosecond units in one second. Requirements
Windows NT/2000/XP: Included in Windows NT 3.5 and later.
Windows 95/98/Me: Unsupported.
Header: Declared in Winbase.h; include Windows.h.
Library: Use Kernel32.lib.GetProcessTimes
The GetProcessTimes function retrieves timing information for the specified process. BOOL GetProcessTimes(
HANDLE hProcess, // handle to process
LPFILETIME lpCreationTime, // process creation time
LPFILETIME lpExitTime, // process exit time
LPFILETIME lpKernelTime, // process kernel-mode time
LPFILETIME lpUserTime // process user-mode time
);
Parameters
hProcess
[in] Handle to the process whose timing information is sought. This handle must be created with the PROCESS_QUERY_INFORMATION access right. For more information, see Process Security and Access Rights.
lpCreationTime
[out] Pointer to a FILETIME structure that receives the creation time of the process.
lpExitTime
[out] Pointer to a FILETIME structure that receives the exit time of the process. If the process has not exited, the content of this structure is undefined.
lpKernelTime
[out] Pointer to a FILETIME structure that receives the amount of time that the process has executed in kernel mode. The time that each of the threads of the process has executed in kernel mode is determined, and then all of those times are summed together to obtain this value.
lpUserTime
[out] Pointer to a FILETIME structure that receives the amount of time that the process has executed in user mode. The time that each of the threads of the process has executed in user mode is determined, and then all of those times are summed together to obtain this value.
Return Values
If the function succeeds, the return value is nonzero.If the function fails, the return value is zero. To get extended error information, call GetLastError. Res
All times are expressed using FILETIME data structures. Such a structure contains two 32-bit values that combine to form a 64-bit count of 100-nanosecond time units. Process creation and exit times are points in time expressed as the amount of time that has elapsed since midnight on January 1, 1601 at Greenwich, England. There are several functions that an application can use to convert such values to more generally useful forms. Process kernel mode and user mode times are amounts of time. For example, if a process has spent one second in kernel mode, this function will fill the FILETIME structure specified by lpKernelTime with a 64-bit value of ten million. That is the number of 100-nanosecond units in one second. Requirements
Windows NT/2000/XP: Included in Windows NT 3.5 and later.
Windows 95/98/Me: Unsupported.
Header: Declared in Winbase.h; include Windows.h.
Library: Use Kernel32.lib.
__int64 lfreq;
BOOL bret=QueryPerformanceFrequency((LARGE_INTEGER*)&lfreq);
__int64 lstart;
QueryPerformanceCounter((LARGE_INTEGER*)&lstart);
......
//at the end, get the end time
__int64 lstop;
QueryPerformanceCounter((LARGE_INTEGER*)&lstop);__int64 lruntime=lstop - lstart;
double dsec= lruntime/lfreq;