how kernel handles sharedmemory

[Blesson Paul]

hi
                  I am surprised how kernel handles the shared memory. When I
give issues shmget command, a sharedmemory is created and id is returned. then
I can use that sharememory by assigning to a charector array. 
                       Now in my situation, presently there is a two
dimensional array. I want to put the whole array in the shared memory. This is
because I need to share this array between the processes. So what I done is ,
I created a linklistin sharememory. But it is not working. I am giving a
sample program. Will anyone can 

#include <sys/shm.h>
typedef struct Alligned
{
        int count1;
        int count2;
        int count3;
}Alligned_pair;

char* share_alloc(int size);
Alligned_pair **m_alligned_pair;

int main()
{
        int shmid,count,childpids[1000],pid;
        Alligned_pair *s,**q;
        m_alligned_pair=(Alligned_pair**)share_alloc(1000*sizeof(Alligned_pair*));
         
        
        for(count=0;count<10;count++)
        {
                pid=fork();
                
                if (pid==0)
                {
                        s=(Alligned_pair*)share_alloc(sizeof(Alligned_pair));
                        s->count1=count;
                        m_alligned_pair[count]=s;       
                        pid=getppid();
                        waitpid(pid,0,0);
                        exit(0);
                }
                        

                else
                {
                        childpids[count]=pid;
                }
        }
        sleep(2);
        for(count = 0; count<20; count++)
        {
                printf("%d    %d\n",m_alligned_pair[count],
m_alligned_pair[count]->count1);
        }
        return 1;
}       


char* share_alloc(int size)
{
        int shmid;
        char *SArray;
        shmid=shmget(random(),size,IPC_CREAT|777);
        SArray=shmat(shmid,0,0);
        return SArray;
}
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