vfork_test.cpp

Linux process and thread programming

#include <iostream>
#include <string>

// Required by for routine
#include <sys/types.h>
#include <unistd.h>
using namespace std;
int globalVariable = 2;

main()
{
    string sIdentifier;
    int    iStackVariable = 20;

    pid_t pID = vfork();
    if (pID == 0)                // child
    {
          // Code only executed by child process
        sIdentifier = "Child Process: ";
        globalVariable++;
        iStackVariable++;
        cout << sIdentifier;
        cout << " Global variable: " << globalVariable;
        cout << " Stack variable: "  << iStackVariable << endl;
         _exit(0);
    }
    else if (pID < 0)            // failed to fork
    {
        cerr << "Failed to fork" << endl;
        exit(1);
        // Throw exception
    }
    else                           // parent
    {
       // Code only executed by parent process
        sIdentifier = "Parent Process:";
    }

   // executed only by parent
    cout << sIdentifier;
    cout << " Global variable: " << globalVariable;
    cout << " Stack variable: "  << iStackVariable << endl;
    int temp = getpid();
    cout<<"pid:"<<temp<<endl;
    exit(0);
                                                                                 }