【发布时间】:2012-01-22 08:12:13
【问题描述】:
我一直在尝试用 C++ 编写一个程序,该程序将在后台监视正在运行的进程,并在检测到某个进程正在运行时终止某个进程。我已经编写了一个可以这样做的程序,但是我能想到的唯一方法是使用无限的WHILE 循环来不断检查程序。正如您可以想象的那样,这会不断地使用 CPU 功率和资源来不断循环。在任务管理器中,您可以看到大多数正在运行的进程始终使用 0% 的 CPU。我的问题是:我如何编写或修改这个程序以在后台运行,利用 0% 的 CPU 直到它检测到它应该终止的进程?
我的整个程序如下。在这个例子中,我在WinMain 中使用了“Notepad.exe”作为程序应该终止的进程。
#include <Windows.h>
#include <iostream>
#include <tlhelp32.h>
#include <string>
#define TA_FAILED 0
#define TA_SUCCESS_CLEAN 1
#define TA_SUCCESS_KILL 2
DWORD WINAPI TerminateApp(DWORD dwPID, DWORD dwTimeout);
DWORD WINAPI Terminate16App(DWORD dwPID, DWORD dwThread, WORD w16Task, DWORD dwTimeout);
typedef struct {
DWORD dwID;
DWORD dwThread;
} TERMINFO;
BOOL CALLBACK TerminateAppEnum( HWND hwnd, LPARAM lParam ) ;
DWORD WINAPI TerminateApp( DWORD dwPID, DWORD dwTimeout ) {
HANDLE hProc ;
DWORD dwRet ;
// If we can't open the process with PROCESS_TERMINATE rights,
// then we give up immediately.
hProc = OpenProcess(SYNCHRONIZE|PROCESS_TERMINATE, FALSE,
dwPID);
if(hProc == NULL) {
return TA_FAILED ;
}
// TerminateAppEnum() posts WM_CLOSE to all windows whose PID
// matches your process's.
EnumWindows((WNDENUMPROC)TerminateAppEnum, (LPARAM) dwPID) ;
// Wait on the handle. If it signals, great. If it times out,
// then you kill it.
if(WaitForSingleObject(hProc, dwTimeout)!=WAIT_OBJECT_0)
dwRet=(TerminateProcess(hProc,0)?TA_SUCCESS_KILL:TA_FAILED);
else
dwRet = TA_SUCCESS_CLEAN ;
CloseHandle(hProc) ;
return dwRet ;
}
BOOL CALLBACK TerminateAppEnum( HWND hwnd, LPARAM lParam ) {
DWORD dwID ;
GetWindowThreadProcessId(hwnd, &dwID) ;
if(dwID == (DWORD)lParam) {
PostMessage(hwnd, WM_CLOSE, 0, 0) ;
}
return TRUE ;
}
DWORD FindProcessId(const std::string& processName);
int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow) {
std::string process1 = "Notepad.exe";
while (1) {
TerminateApp(FindProcessId(process1),0);
}
return 0;
}
DWORD FindProcessId(const std::string& processName) {
PROCESSENTRY32 processInfo;
processInfo.dwSize = sizeof(processInfo);
HANDLE processesSnapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, NULL);
if (processesSnapshot == INVALID_HANDLE_VALUE) {
return 0;
}
Process32First(processesSnapshot, &processInfo);
if (!processName.compare(processInfo.szExeFile)) {
CloseHandle(processesSnapshot);
return processInfo.th32ProcessID;
}
while (Process32Next(processesSnapshot, &processInfo)) {
if (!processName.compare(processInfo.szExeFile)) {
CloseHandle(processesSnapshot);
return processInfo.th32ProcessID;
}
}
CloseHandle(processesSnapshot);
return 0;
}
【问题讨论】:
-
在 while(1) 循环中的快速修复是
Sleep(1)。不要犹豫,让它变大,但 1 已经足以让它接近零。 -
啊哈,谢谢 Hans Passant 的建议。这完全解决了我的问题!也感谢 parapura rajkumar 的建议!
标签: windows background process monitor terminate