第一个
API
：创建一个线程
CreateThread()
The CreateThread function creates a thread to execute within the address space of the calling process.
HANDLE CreateThread(
LPSECURITY_ATTRIBUTES lpThreadAttributes, // pointer to thread security attributes
DWORD dwStackSize, // initial thread stack size, in bytes
LPTHREAD_START_ROUTINE lpStartAddress, // pointer to thread function
LPVOID lpParameter,// argument for new thread
DWORD dwCreationFlags, // creation flags
LPDWORD lpThreadId // pointer to returned thread identifier
);
Return Values
If the function succeeds, the return value is a handle to the new thread.
If the function fails, the return value is NULL. To get extended error information, call etLastError.
Example1:
创建一个线程
#include
<windows.h>
DWORD
WINAPI
threadFunc (LPVOIDpArg)
{
return 0;
}
main
()
{
HANDLE
hThread;
hThread = CreateThread (NULL, 0, threadFunc, NULL, 0, NULL );
return 0;
}
上面这段代码有一个小问题，那就是
threadFunc
有可能不会被执行到就结束了！要保证
threadFunc
肯定被执行（也就是等线程退出），在
CreateThread
后加一行代码：
WaitForMultipleObjects
(1, &hThread, TRUE, INFINITE);
第二个
API
：等待线程返回
WaitForMultipleObjects
The WaitForMultipleObjects function returns when one of the following occurs:
Either any one or all of the specified objects are in the signaled state.
The time-out interval elapses.
DWORD WaitForMultipleObjects(
DWORD nCount, // number of handles in the object handle array
CONST HANDLE *lpHandles, // pointer to the object-handle array
BOOL bWaitAll, // wait flag
DWORD dwMilliseconds // time-out interval in milliseconds
);
If dwMilliseconds is INFINITE, the function's time-out interval never elapses.
Example2:
四个线程一起运行
#include
<Windows.h>
#include
<stdio.h>
const
int
numThreads = 4;
DWORD
WINAPI
threadFunc(LPVOIDpArg)
{
int *p = (int *)pArg;
int
num = *p;
printf("threadFunc...%d...\n", num);
return 0;
}
int
main()
{
HANDLE
hThread[numThreads];
int
threadNum[numThreads];
for(inti=0; i<numThreads; i++)
{
threadNum[i] = i;
hThread[i] = CreateThread(NULL, 0, threadFunc, &threadNum[i], 0, NULL);
}
WaitForMultipleObjects(numThreads, hThread, TRUE, INFINITE);
return 0;
}