How can you extract SIGINFO information for signal trap subroutines? Here's a snippet of what it would include:

       The siginfo_t parameter to sa_sigaction is a struct with the fo
+llowing elements

              siginfo_t {
                  int      si_signo;  /* Signal number */
                  int      si_errno;  /* An errno value */
                  int      si_code;   /* Signal code */
                  pid_t    si_pid;    /* Sending process ID */
                  uid_t    si_uid;    /* Real user ID of sending proce
+ss */
                  int      si_status; /* Exit value or signal */
                  clock_t  si_utime;  /* User time consumed */
                  clock_t  si_stime;  /* System time consumed */
                  sigval_t si_value;  /* Signal value */
                  int      si_int;    /* POSIX.1b signal */
                  void *   si_ptr;    /* POSIX.1b signal */
                  void *   si_addr;   /* Memory location which caused 
+fault */
                  int      si_band;   /* Band event */
                  int      si_fd;     /* File descriptor */
              }
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I've digged and digged around on the net for something that works, but can't find anything. The closest I've found is something like this:

use POSIX;
sub hup {
    print "hup(@_)\n";
    for my $k (sort keys %{$_[1]}) {
        print "$k $_[1]->{$k}\n";
    }
}
my $newaction=POSIX::SigAction->new(\&hup, 0, SA_SIGINFO);
sigaction(SIGHUP, $newaction);
print "I am $$\n";
kill HUP, $$;
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However, it doesn't work on the Knoppix Linux distro that I tried. It acts like a typical $SIG trap, and doesn't return anything except the signal type.

Also, is there any reason why this sort of thing wouldn't be built into Perl in the first place? It would seem like a well requested thing to at least know which process ID sent a TERM signal, for example.