cat prime.f
/* prime.f May 3, 1987 */
prime(h) /* Interacts with user to generate a prime suitable to be a factor in the
the product that becomes the masterkey.  Called twice, generates two factors */
char *h ;
{       char *x, *y, *z, *malloc() ;
        char f1, f2 ;
        x = malloc(15) ;
        y = malloc(15) ;
        z = malloc(15) ;
        copy(xero,x) ;
        copy(xero,y) ;
        copy(xero,z) ;
        f1 = 'y' ;
        while( f1 == 'y')
        {       printf("\nEnter a prime number seed.") ;
                scanf("\n %s",x) ;
                printf("\nEnter a starting number") ;
                scanf("\n %s",y) ;
                printf("\n") ;
                pad(x) ;
                pad(y) ;
                printf("seed is %s, starting search at  %s\n", x,y) ;
                f2 = 'y' ;
                while(f2 == 'y' )
                {       search(y,x,z) ;
                        printf("%s is a prime, new search starts at  %s \n", z,y) ;
                        add(y,one) ;
                        printf("Continue this search? y/n \n") ;
                        scanf("\n%c",&f2) ;
                }
                printf("\nAnother search? y/n\n") ;
                scanf("\n %c",&f1) ;
        }
        copy(z,h) ;
}

$