使用CreateThread建立线程池的步骤
使用CreateThread建立线程池的步骤
下面是关于createthread在cb6中的帮助：
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
);
Parameters
lpThreadAttributes
Pointer to a SECURITY_ATTRIBUTES structure that determines whether the returned handle can be inherited by child processes. If lpThreadAttributes is NULL, the handle cannot be inherited.
Windows NT: The lpSecurityDescriptor member of the structure specifies a security descriptor for the new thread. If lpThreadAttributes is NULL, the thread gets a default security descriptor.
Windows 95: The lpSecurityDescriptor member of the structure is ignored.
dwStackSize
Specifies the size, in bytes, of the stack for the new thread. If 0 is specified, the stack size defaults to the same size as that of the primary thread of the process. The stack is allocated automatically in the memory space of the process and it is freed when the thread terminates. Note that the stack size grows, if necessary.
CreateThread tries to commit the number of bytes specified by dwStackSize, and fails if the size exceeds available memory.
lpStartAddress
The starting address of the new thread. This is typically the address of a function declared with the WINAPI calling convention that accepts a single 32-bit pointer as an argument and returns a 32-bit exit code. Its prototype is:
DWORD WINAPI ThreadFunc( LPVOID );
lpParameter
Specifies a single 32-bit parameter value passed to the thread.
dwCreationFlags
Specifies additional flags that control the creation of the thread. If the CREATE_SUSPENDED flag is specified, the thread is created in a suspended state, and will not run until the ResumeThread function is called. If this value is zero, the thread runs immediately after creation. At this time, no other values are supported.
lpThreadId
Points to a 32-bit variable that receives the 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 GetLastError.
Remarks
The new thread handle is created with full access to the new thread. If a security descriptor is not provided, the handle can be used in any function that requires a thread object handle. When a security descriptor is provided, an access check is performed on all subsequent uses of the handle before access is granted. If the access check denies access, the requesting process cannot use the handle to gain access to the thread.
The thread execution begins at the function specified by the lpStartAddress parameter. If this function returns, the DWORD return value is used to terminate the thread in an implicit call to the ExitThread function. Use the GetExitCodeThread function to get the thread's return value.
The CreateThread function may succeed even if lpStartAddress points to data, code, or is not accessible. If the start address is invalid when the thread runs, an exception occurs, and the thread terminates. Thread termination due to a invalid start address is handled as an error exit for the thread's process. This behavior is similar to the asynchronous nature of CreateProcess, where the process is created even if it refers to invalid or missing dynamic-link libraries (DLLs).
The thread is created with a thread priority of THREAD_PRIORITY_NORMAL. Use the GetThreadPriority and SetThreadPriority functions to get and set the priority value of a thread.
When a thread terminates, the thread object attains a signaled state, satisfying any threads that were waiting on the object.
The thread object remains in the system until the thread has terminated and all handles to it have been closed through a call to CloseHandle.
The ExitProcess, ExitThread, CreateThread, CreateRemoteThread functions, and a process that is starting (as the result of a call by CreateProcess) are serialized between each other within a process. Only one of these events can happen in an address space at a time. This means that the following restrictions hold:
?During process startup and DLL initialization routines, new threads can be created, but they do not begin execution until DLL initialization is done for the process.
?Only one thread in a process can be in a DLL initialization or detach routine at a time.
?ExitProcess does not return until no threads are in their DLL initialization or detach routines.
A thread that uses functions from the C run-time libraries should use the beginthread and endthread C run-time functions for thread management rather than CreateThread and ExitThread. Failure to do so results in small memory leaks when ExitThread is called.
在我同事搞嵌入式的讨论中得到对线程池的应用
下面是使用单一挂起线程的代码
#include<stdio.h>
#include"windows.h"
#pragma hdrstop
#defineRECV_THREAD_LPSECURITY(LPSECURITY_ATTRIBUTES)0// 安全属性
#defineRECV_THREAD_STACK_SIZE64 * 1024// 堆栈大小
#defineRECV_THREAD_HANDLE(LPTHREAD_START_ROUTINE)thread_recv// 线程代码
#defineRECV_THREAD_PARAM(LPVOID)0
#defineRECV_THREAD_FLAG(DWORD)0
DWORDRecvThreadId;// ID
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
intsk;// socket
charbuf[100];// recv_buf
intrecv_num;// recv_num
struct sockaddr_inlocal_addr;// local_addr
struct sockaddr_inremote_addr;// remote_addr
intaddr_in_size;// sizeof(struct sockaddr_in)
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
voidthread_recv (void *arg);
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
#pragma argsused
int main(int argc, char* argv[])
{
/* 建立线程 */
CreateThread(RECV_THREAD_LPSECURITY,
RECV_THREAD_STACK_SIZE,
RECV_THREAD_HANDLE,
RECV_THREAD_PARAM,
RECV_THREAD_FLAG,
&RecvThreadId0
);
while (1) {
Sleep(100);
}
return 1;
}
//---------------------------------------------------------------------------
voidthread_recv (void *arg)
{
while (1) {
printf("aaaa/n");
Sleep(1000);
}
}
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
//在和同事们的讨论中讨论到线程池问题，线程池就是把相同的代码映射到不同的线程执行。代码如下
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
#include<stdio.h>
#include"windows.h"
#pragma hdrstop
#defineRECV_THREAD_LPSECURITY(LPSECURITY_ATTRIBUTES)0// 安全属性
#defineRECV_THREAD_STACK_SIZE64 * 1024// 堆栈大小
#defineRECV_THREAD_HANDLE(LPTHREAD_START_ROUTINE)thread_recv// 线程代码
#defineRECV_THREAD_PARAM(LPVOID)0
#defineRECV_THREAD_FLAG(DWORD)0
DWORDRecvThreadId0;// ID
DWORDRecvThreadId1;// ID
DWORDRecvThreadId2;// ID
DWORDRecvThreadId3;// ID
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
intsk;// socket
charbuf[100];// recv_buf
intrecv_num;// recv_num
struct sockaddr_inlocal_addr;// local_addr
struct sockaddr_inremote_addr;// remote_addr
intaddr_in_size;// sizeof(struct sockaddr_in)
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
voidthread_recv (void *arg);
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
#pragma argsused
int main(int argc, char* argv[])
{
/* 建立线程池 */
CreateThread(RECV_THREAD_LPSECURITY,
RECV_THREAD_STACK_SIZE,
RECV_THREAD_HANDLE,
RECV_THREAD_PARAM,
RECV_THREAD_FLAG,
&RecvThreadId0
);
CreateThread(RECV_THREAD_LPSECURITY,
RECV_THREAD_STACK_SIZE,
RECV_THREAD_HANDLE,
RECV_THREAD_PARAM,
RECV_THREAD_FLAG,
&RecvThreadId1
);
CreateThread(RECV_THREAD_LPSECURITY,
RECV_THREAD_STACK_SIZE,
RECV_THREAD_HANDLE,
RECV_THREAD_PARAM,
RECV_THREAD_FLAG,
&RecvThreadId2
);
CreateThread(RECV_THREAD_LPSECURITY,
RECV_THREAD_STACK_SIZE,
RECV_THREAD_HANDLE,
RECV_THREAD_PARAM,
RECV_THREAD_FLAG,
&RecvThreadId3
);
while (1) {
Sleep(100);
}
return 1;
}
//---------------------------------------------------------------------------
voidthread_recv (void *arg)
{
while (1) {
printf("aaaa/n");
Sleep(1000);
}
}