via Snapshot

Here we will find PID of process by CreateToolhelp32Snapshot() function.

Code

---

//hack.cpp
#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <tlhelp32.h>
 
// find process ID by process name
int findMyProc(const char *procname) {
	HANDLE hSnapshot;
	PROCESSENTRY32 pe;
	int pid = 0;
	BOOL hResult;
	
	// snapshot of all processes in the system
	hSnapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
	if (INVALID_HANDLE_VALUE == hSnapshot) return 0;
	
	// initializing size: needed for using Process32First
	pe.dwSize = sizeof(PROCESSENTRY32);
	
	// info about first process encountered in a system snapshot
	hResult = Process32First(hSnapshot, &pe);
	
	// retrieve information about the processes
	// and exit if unsuccessful
	while (hResult) {
		// if we find the process: return process ID
		if (strcmp(procname, pe.szExeFile) == 0) {
			pid = pe.th32ProcessID;
			break;
		}
		hResult = Process32Next(hSnapshot, &pe);
	}
	// closes an open handle (CreateToolhelp32Snapshot)
	CloseHandle(hSnapshot);
	return pid;
}
int main(int argc, char* argv[]) {
	int pid = 0; // process ID
	pid = findMyProc(argv[1]);
	if (pid) {
		printf("PID = %d\n", pid);
	}
	return 0;
}