Is the linux thread protected?

Whether linux threads are protected-Linux general technology-Linux programming and kernel information. For details, refer to the following section. In linux, the threads under the same process are in the same process space. Is there any problem of cross-border access?

I just did a test. The answer is: there is a cross-border problem.

[Root @ FC5 thread] # gcc-o hk hookpthread. c-lpthread;./hk; cat hookpthread. c
& A: [b7f77464] ----- a: [20]
& B: [b7576464]
Hook --> & a: [20]
& A: [b7f77464] ----- a: [30]
# Include
# Include
Void * fun (void * I)
{
Int a = 20;
Printf ("& a: [% x] ----- a: [% d] \ n", & a, );
Sleep (1 );
Printf ("& a: [% x] ----- a: [% d] \ n", & a, );
Pthread_exit (NULL );

}

Void * hook (void *)
{
Int B = 10;
Printf ("& B: [% x] \ n", & B );
Printf ("hook --> & a: [% d] \ n", * (& B + 2622464 ));
* (& B + 2622464) = 30;
Pthread_exit (NULL );

}
Int main ()
{
Pthread_t pidfun, pidhook;
Pthread_create (& pidfun, NULL, fun, NULL );
Pthread_create (& pidhook, NULL, hook, NULL );
Sleep (2 );
Return 0;
}