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/* ISC license. */
#include <unistd.h>
#include <sys/types.h>
#include <fcntl.h>
#include <errno.h>
static int fd_read (int fd, char *buf, unsigned int len)
{
register int r ;
do r = read(fd, buf, len) ;
while ((r == -1) && (errno == EINTR)) ;
return r ;
}
static unsigned int allread (int fd, register char *buf, register unsigned int len)
{
register unsigned int written = 0 ;
while (len)
{
register int w = fd_read(fd, buf, len) ;
if (!w) errno = EPIPE ;
if (w <= 0) break ;
written += w ;
buf += w ;
len -= w ;
}
return written ;
}
static int byte_diff (char *s, unsigned int n, char *t)
{
for (;;)
{
if (!n) return 0 ;
if (*s != *t) break ;
++s ; ++t ; --n ;
}
return ((int)(unsigned int)(unsigned char) *s)
- ((int)(unsigned int)(unsigned char) *t);
}
int main ()
{
char a[64] ;
char b[64] ;
int fd = open("/dev/random", O_RDONLY) ;
if ((fd == -1) || (allread(fd, a, 64) < 64) ) return 111 ;
close(fd) ;
fd = open("/dev/random", O_RDONLY) ;
if ((fd == -1) || (allread(fd, b, 64) < 64) ) return 111 ;
close(fd) ;
return !byte_diff(a, 64, b) ;
}
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