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我使用下面的代碼從微軟作爲一個模板：如何使用Windows API直接「分配」進程到信號量？
#include <windows.h>
#include <stdio.h>
#define MAX_SEM_COUNT 10
#define THREADCOUNT 12
HANDLE ghSemaphore;
DWORD WINAPI ThreadProc(LPVOID);
int main(void)
{
HANDLE aThread[THREADCOUNT];
DWORD ThreadID;
int i;
// Create a semaphore with initial and max counts of MAX_SEM_COUNT
ghSemaphore = CreateSemaphore(
NULL, // default security attributes
MAX_SEM_COUNT, // initial count
MAX_SEM_COUNT, // maximum count
NULL); // unnamed semaphore
if (ghSemaphore == NULL)
{
printf("CreateSemaphore error: %d\n", GetLastError());
return 1;
}
// Create worker threads
for(i=0; i < THREADCOUNT; i++)
{
aThread[i] = CreateThread(
NULL, // default security attributes
0, // default stack size
(LPTHREAD_START_ROUTINE) ThreadProc,
NULL, // no thread function arguments
0, // default creation flags
&ThreadID); // receive thread identifier
if(aThread[i] == NULL)
{
printf("CreateThread error: %d\n", GetLastError());
return 1;
}
}
// Wait for all threads to terminate
WaitForMultipleObjects(THREADCOUNT, aThread, TRUE, INFINITE);
// Close thread and semaphore handles
for(i=0; i < THREADCOUNT; i++)
CloseHandle(aThread[i]);
CloseHandle(ghSemaphore);
return 0;
}
DWORD WINAPI ThreadProc(LPVOID lpParam)
{
// lpParam not used in this example
UNREFERENCED_PARAMETER(lpParam);
DWORD dwWaitResult;
BOOL bContinue=TRUE;
while(bContinue)
{
// Try to enter the semaphore gate.
dwWaitResult = WaitForSingleObject(
ghSemaphore, // handle to semaphore
0L); // zero-second time-out interval
switch (dwWaitResult)
{
// The semaphore object was signaled.
case WAIT_OBJECT_0:
// TODO: Perform task
printf("Thread %d: wait succeeded\n", GetCurrentThreadId());
bContinue=FALSE;
// Simulate thread spending time on task
Sleep(5);
// Release the semaphore when task is finished
if (!ReleaseSemaphore(
ghSemaphore, // handle to semaphore
1, // increase count by one
NULL)) // not interested in previous count
{
printf("ReleaseSemaphore error: %d\n", GetLastError());
}
break;
// The semaphore was nonsignaled, so a time-out occurred.
case WAIT_TIMEOUT:
printf("Thread %d: wait timed out\n", GetCurrentThreadId());
break;
}
}
return TRUE;
}
我要去適應它，而不是作爲線程確定旗語如何填充的，它是由程序完成的，也就是說，如果有進程正在運行，並且/或者它們的任何哈希都沒有關閉，那麼信號量就會被填充，事實上，我通過使用這個新函數改變了線程函數的工作方式。
DWORD WINAPI ThreadProc(LPVOID lpParam)
{
// lpParam not used in this example
UNREFERENCED_PARAMETER(lpParam);
DWORD dwWaitResult;
BOOL bContinue=TRUE;
STARTUPINFO si;
PROCESS_INFORMATION pi;
memset(&si,0,sizeof(si));
si.cb=sizeof(si);
while(bContinue)
{
// Try to enter the semaphore gate.
dwWaitResult = WaitForSingleObject(
ghSemaphore, // handle to semaphore
0L); // zero-second time-out interval
CreateProcess("arbol.exe",NULL,NULL,NULL,0,0,NULL,NULL,&si,&pi);
WaitForSingleObject(pi.hProcess,INFINITE);
CloseHandle(pi.hProcess);
CloseHandle(pi.hThread);
switch (dwWaitResult)
{
// The semaphore object was signaled.
case WAIT_OBJECT_0:
// TODO: Perform task
printf("Thread %d: wait succeeded\n", GetCurrentThreadId());
bContinue=FALSE;
// Simulate thread spending time on task
Sleep(5);
// Release the semaphore when task is finished
if (!ReleaseSemaphore(
ghSemaphore, // handle to semaphore
1, // increase count by one
NULL)) // not interested in previous count
{
printf("ReleaseSemaphore error: %d\n", GetLastError());
}
break;
// The semaphore was nonsignaled, so a time-out occurred.
case WAIT_TIMEOUT:
printf("Thread %d: wait timed out\n", GetCurrentThreadId());
break;
}
}
return TRUE;
}
隨着的是，雖然什麼決定了信號量的填充是單線程的，在實際意義上它是由該方法的手柄的完整執行和關閉來確定。
但是，這看起來是一個蹩腳的方式來解決這個問題，我敢打賭這樣做可能會給未來的問題，如果需要額外的東西從這些過程。
我該如何創建一個信號量，才能真正確定信號量的填充是什麼過程？爲了澄清，這將是一個可能的解決方案，我不認爲這是可能的。
讓我們考慮一下，你可以通過這樣的創建過程：
aThread[i] = CreateProcess(
NULL, // default security attributes
0, // default stack size
(LPTHREAD_START_ROUTINE) ThreadProc,
NULL, // no thread function arguments
0, // default creation flags
&ThreadID); // receive thread identifier
然後LPTHREAD_START_ROUTINE將是其工作但過程相當的。
信號量應該支持Interprocess Synchronization在Windows API中，但我找不到任何具體使用進程的示例，我不知道它是如何完成的。
關於如何實現我想要的任何想法？
問候。