Programming

for(c=0;c<(argc-1) && (c==0 || child[c-1].pid!=0);c++){
            if ((child[c].pid = fork()) < 0){
                  perror("fork error");
                  exit(1);
            }  
        child[c].N=atoi(argv[c+1]);
    }

pid_t pid =0;
int i=0;
int status=0;
for(i=0< i< 10; i++)
{
     pid=fork();
     switch (pid)
     {
          case 0:  // this is the child process
               // work with the process here
               // 
               exit(0);   // do not get out of this block of code in the child
               break;
          case -1:  // error
               perror("failed to fork a new process");
               exit(1);
               break;
          default:  // parent process  
              
     }
     // wait for the kids to exit
     errno=0;
     // when no more children wait reutrns -1 and sets errno to ECHILD
     while( (pid=wait(&status) )>0 );
     if(errno==ECHILD)
        exit(0);
     else
     {
        perror("Error waiting for child");
        exit(1);
      }
}