Programming

	
        #include <sys/types.h>
	#include <unistd.h>			
	#include <iostream>
	#include <pthread.h>
	#include<cstring>
	using namespace std;

	

	int var1=0;  
   
	void doSomething()  
	{
		var1 = 5;
		cout<<"Do S :"<<var1<<endl;	
		sleep(1);
		var1 =7;

		cout<<"Do S :"<<var1<<endl;	
		sleep(1);

		var1 =10;
		cout<<"Do S l :"<<var1<<endl;	
		sleep(1);
     
	 }  
   
	int main()  
	 {  
   
	     if (fork() != 0)  
		     doSomething();   
		 else
		     {
			cout << var1 << endl; sleep(1);
			cout << var1 << endl; sleep(1);
			cout << var1 << endl; sleep(1);
			cout << var1 << endl; sleep(1);
			}
   
		  return 0;  
	 }

#include <sys/mman.h>
#include <sys/types.h>
#include <unistd.h>
#include <iostream>
#include <pthread.h>
#include<cstring>
using namespace std;

int *mem=(int *)MAP_FAILED;

#define var1 (mem[0])

void doSomething()
{
        var1 = 5;
        cout<<"Do S :"<<var1<<endl;
        sleep(1);
        var1 =7;

        cout<<"Do S :"<<var1<<endl;
        sleep(1);
        var1 =10;
        cout<<"Do S l :"<<var1<<endl;
        sleep(1);
}

int main()
{
        // Create shared memory.  Has to be done in blocks of pagesize.
        // So it could probably hold lots of integers, not just one.
        mem=(int *)mmap(NULL, getpagesize(), PROT_READ|PROT_WRITE,
                MAP_SHARED|MAP_ANONYMOUS, -1, 0);
        if(mem == MAP_FAILED)
                return(1);

        if (fork() != 0)
             doSomething();
        else
        {
                cout << var1 << endl; sleep(1);
                cout << var1 << endl; sleep(1);
                cout << var1 << endl; sleep(1);
                cout << var1 << endl; sleep(1);
        }

        return 0;
}