#include <stdio.h>
#include <stdlib.h>
int main()
{ int pid; printf("1) before the fork\n"); pid = fork(); printf("2) after the fork\n"); if (pid == 0) { printf("3) i am the child process, my pid is %d\n", getpid()); printf("my parent has the pid %d\n", getppid()); exit(1); } else { printf("i am the parent process, my pid is %d\n", getpid()); printf("my parent has the pid %d\n", getppid()); exit(0); //the father of the father is the terminal }
}
// THIS ONLY WORKS ON LINUX

/* Windows only */
#include <stdio.h>
#include <Windows.h>
#include <TlHelp32.h>
int
main(void)
{	const WCHAR *processname = L"name_of_your_process.exe";	DWORD pid = 0;	HANDLE snapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);	PROCESSENTRY32 process;	ZeroMemory(&process, sizeof(process));	process.dwSize = sizeof(process);	if (Process32First(snapshot, &process)) {	do {	if (!wcscmp(process.szExeFile, processname)) {	pid = process.th32ProcessID;	break;	}	} while (Process32Next(snapshot, &process));	}	CloseHandle(snapshot); /* rest of code */ /* pid of our target is stored in the "pid" DWORD */	return 0;
}