How can I get a process handle by its name in C++?
C++WinapiProcessC++ Problem Overview
I'm trying to get the process handle of, say example.exe, so I can call TerminateProcess
on it. How can I do this? Notice, it doesn't have a window so FindWindow
won't work.
C++ Solutions
Solution 1 - C++
#include <cstdio>
#include <windows.h>
#include <tlhelp32.h>
int main( int, char *[] )
{
PROCESSENTRY32 entry;
entry.dwSize = sizeof(PROCESSENTRY32);
HANDLE snapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, NULL);
if (Process32First(snapshot, &entry) == TRUE)
{
while (Process32Next(snapshot, &entry) == TRUE)
{
if (stricmp(entry.szExeFile, "target.exe") == 0)
{
HANDLE hProcess = OpenProcess(PROCESS_ALL_ACCESS, FALSE, entry.th32ProcessID);
// Do stuff..
CloseHandle(hProcess);
}
}
}
CloseHandle(snapshot);
return 0;
}
Also, if you'd like to use PROCESS_ALL_ACCESS in OpenProcess, you could try this:
#include <cstdio>
#include <windows.h>
#include <tlhelp32.h>
void EnableDebugPriv()
{
HANDLE hToken;
LUID luid;
TOKEN_PRIVILEGES tkp;
OpenProcessToken(GetCurrentProcess(), TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY, &hToken);
LookupPrivilegeValue(NULL, SE_DEBUG_NAME, &luid);
tkp.PrivilegeCount = 1;
tkp.Privileges[0].Luid = luid;
tkp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
AdjustTokenPrivileges(hToken, false, &tkp, sizeof(tkp), NULL, NULL);
CloseHandle(hToken);
}
int main( int, char *[] )
{
EnableDebugPriv();
PROCESSENTRY32 entry;
entry.dwSize = sizeof(PROCESSENTRY32);
HANDLE snapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, NULL);
if (Process32First(snapshot, &entry) == TRUE)
{
while (Process32Next(snapshot, &entry) == TRUE)
{
if (stricmp(entry.szExeFile, "target.exe") == 0)
{
HANDLE hProcess = OpenProcess(PROCESS_ALL_ACCESS, FALSE, entry.th32ProcessID);
// Do stuff..
CloseHandle(hProcess);
}
}
}
CloseHandle(snapshot);
return 0;
}
Solution 2 - C++
The following code shows how you can use toolhelp and OpenProcess to get a handle to the process. Error handling removed for brevity.
HANDLE GetProcessByName(PCSTR name)
{
DWORD pid = 0;
// Create toolhelp snapshot.
HANDLE snapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
PROCESSENTRY32 process;
ZeroMemory(&process, sizeof(process));
process.dwSize = sizeof(process);
// Walkthrough all processes.
if (Process32First(snapshot, &process))
{
do
{
// Compare process.szExeFile based on format of name, i.e., trim file path
// trim .exe if necessary, etc.
if (string(process.szExeFile) == string(name))
{
pid = process.th32ProcessID;
break;
}
} while (Process32Next(snapshot, &process));
}
CloseHandle(snapshot);
if (pid != 0)
{
return OpenProcess(PROCESS_ALL_ACCESS, FALSE, pid);
}
// Not found
return NULL;
}
Solution 3 - C++
There are two basic techniques. The first uses PSAPI; MSDN has an example that uses EnumProcesses
, OpenProcess
, EnumProcessModules
, and GetModuleBaseName
.
The other uses Toolhelp, which I prefer. Use CreateToolhelp32Snapshot
to get a snapshot of the process list, walk over it with Process32First
and Process32Next
, which provides module name and process ID, until you find the one you want, and then call OpenProcess
to get a handle.
Solution 4 - C++
The following code can be used:
DWORD FindProcessId(const std::wstring& 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;
}
Usage:
auto processId = FindProcessId(L"blabla.exe");
Getting a handle should be obvious, just call OpenProcess()
or similar on it.
Solution 5 - C++
Check out: http://msdn.microsoft.com/en-us/library/ms682489(VS.85).aspx">MSDN Article
You can use GetModuleName
(I think?) to get the name and check against that.
Solution 6 - C++
OpenProcess Function
From MSDN:
To open a handle to another local process and obtain full access rights, you must enable the SeDebugPrivilege privilege.
Solution 7 - C++
If you don't mind using system()
, doing system("taskkill /f /im process.exe")
would be significantly easier than these other methods.