unsigned long rand;

get random bytes(Srand, sizeof(rand));

 ,     , -
   : /dev/random  /dev/urandom.  ,
/dev/random, ,     
      .  -
      ,    -
  .      ,  
 /dev/random     ,   -
,    .  /dev/urandom  
 ,     .   -
       .

      .   
 ,      
  .

unsigned long get_random(void)
{

unsigned long seed = 0;

int fd;

fd = open("/dev/urandom", 0_RDONLY) ;

if (fd == -1) {

perror("open");

return 0;

}
if (read (fd, &seed, sizeof(seed)) < 0) {

perror("read") ;

seed = 0;

}
if (close(fd))

perror("close") ;

.return seed;

}

   $ bytes    $file,   dd.

dd if=/dev/urandom of=$file count=l bs=$bytes

428  