sigprocmask( ) blocking signals in UNIX

i have written a small piece of code. This code first blocks the {SIGSEGV}, then adds SIGRTMIN to the same set. So, my final signal set is, {SIGSEGV,SIGRTMIN}. Thus, if i use SIG_UNBLOCK, as per my understanding, first SIGRTMIN should be unblocked, and then again if i invoke SIG_UNBLOCK, SIGSEGV should be unblocked.

That is, 1) {SIGSEGV,SIGRTMIN} 2) SIG_UNBLOCK = unblock SIGRTMIN, 3) Again invoke SIG_UNBLOCK = unblock SIGSEGV. Я даю процессу только SIGRTMIN, поэтому моя вторая разблокировка должна остановить процесс с помощью SIGRTMIN. Но это не так. Пожалуйста помоги. NB: Пожалуйста, не давайте ссылки на ответы на другие вопросы по sigprocmask (), я видел их, и они не разъясняют мой вопрос.

enter code here
#include <signal.h>
#include <unistd.h>
#include <stdio.h>

int main()
{
 sigset_t old_set,new_set;
 sigemptyset(&old_set);
 sigemptyset(&new_set);

 if(sigaddset(&old_set,SIGSEGV)==0)
 {
   printf("sigaddset successfully added for SIGSEGV\n");
 }
 sigprocmask(SIG_BLOCK,&old_set,NULL); // SIGSEGV signal is masked
 kill(0,SIGSEGV);


 //*****************************************************************

 if(sigaddset(&new_set,SIGRTMIN)==0)
 {
  printf("sigaddset successfully added for SIGRTMIN\n");
 }
  sigprocmask(SIG_BLOCK,&new_set,&old_set); // SIGRTMIN signal is masked
 kill(0,SIGSEGV);

 //****************** Unblock one signal at a time ******************

 sigprocmask(SIG_UNBLOCK,&new_set,&old_set); // SIGRTMIN signal is unmasked
 sigprocmask(SIG_UNBLOCK,&new_set,&old_set); // SIGSEGV signal is unmasked

}

Output:
 [root@dhcppc0 signals]# ./a.out
  sigaddset successfully added for SIGSEGV
  sigaddset successfully added for SIGRTMIN
  (Note:SIGSEGV is not received even after sigprocmask(SIG_UNBLOCK,&new_set,&old_set); a second time)