How can I get a process handle by its name in C++?

Question

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.

Answer 1

#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; } 

Answer 2

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; }