Fix previous commit. The standards specifically say: "The structure

sigaction, used to describe an action to be taken, is defined in the
header <signal.h> to include at least the following members:"
                             ^^^^^^^^
A sigaction defined on stack with essentially random contents may have
just about anything underneath fields that the program doesn't know about.
It is not safe to delete the bzero.

lib/libc/net/res_send.c

@@ -665,6 +665,7 @@ read_len:
 				pfd.fd = s;
 				pfd.events = POLLIN;
 				if (use_poll == 1) {
+					bzero(&sa, sizeof(sa));
 					sigemptyset(&sa.sa_mask);
 					sa.sa_flags = 0;
 					sa.sa_handler = SIG_IGN;