[NaCl SDK] nacl_io: Add initial implementations of kill and signal

native_client_sdk/src/libraries/nacl_io/kernel_intercept.cc

Index: native_client_sdk/src/libraries/nacl_io/kernel_intercept.cc
diff --git a/native_client_sdk/src/libraries/nacl_io/kernel_intercept.cc b/native_client_sdk/src/libraries/nacl_io/kernel_intercept.cc
index cb517347afa5882839f57d115923017af76bbe6d..180aaf90298286ce57b03364b40e5bdb89974a96 100644
--- a/native_client_sdk/src/libraries/nacl_io/kernel_intercept.cc
+++ b/native_client_sdk/src/libraries/nacl_io/kernel_intercept.cc
@@ -257,6 +257,21 @@ int ki_tcsetattr(int fd, int optional_actions,
   return s_kp->tcsetattr(fd, optional_actions, termios_p);
 }
 
+int ki_kill(pid_t pid, int sig) {
+  ON_NOSYS_RETURN(-1);
+  return s_kp->kill(pid, sig);
+}
+
+sighandler_t ki_signal(int signum, sighandler_t handler) {
+  ON_NOSYS_RETURN(SIG_ERR);
+  return s_kp->signal(signum, handler);
+}
+
+sighandler_t ki_sigset(int signum, sighandler_t handler) {
+  ON_NOSYS_RETURN(SIG_ERR);
+  return s_kp->sigset(signum, handler);
+}
+
 #ifdef PROVIDES_SOCKET_API
 // Socket Functions
 int ki_accept(int fd, struct sockaddr* addr, socklen_t* len) {