diff --git a/unix/unix.h b/unix/unix.h
index 68f749ac..f21d23ff 100644
--- a/unix/unix.h
+++ b/unix/unix.h
@@ -180,7 +180,7 @@ void postmsg(struct termios *);
 /* The interface used by uxsel.c */
 typedef struct uxsel_id uxsel_id;
 void uxsel_init(void);
-typedef int (*uxsel_callback_fn)(int fd, int event);
+typedef void (*uxsel_callback_fn)(int fd, int event);
 void uxsel_set(int fd, int rwx, uxsel_callback_fn callback);
 void uxsel_del(int fd);
 void select_result(int fd, int event);
diff --git a/unix/uxagentc.c b/unix/uxagentc.c
index ffc5879c..51f9a1eb 100644
--- a/unix/uxagentc.c
+++ b/unix/uxagentc.c
@@ -98,7 +98,7 @@ void agent_cancel_query(agent_pending_query *conn)
     sfree(conn);
 }
 
-static int agent_select_result(int fd, int event)
+static void agent_select_result(int fd, int event)
 {
     agent_pending_query *conn;
 
@@ -107,11 +107,11 @@ static int agent_select_result(int fd, int event)
     conn = find234(agent_pending_queries, &fd, agent_connfind);
     if (!conn) {
 	uxsel_del(fd);
-	return 1;
+	return;
     }
 
     if (!agent_try_read(conn))
-	return 0;		       /* more data to come */
+	return;		       /* more data to come */
 
     /*
      * We have now completed the agent query. Do the callback, and
@@ -120,7 +120,6 @@ static int agent_select_result(int fd, int event)
      */
     conn->callback(conn->callback_ctx, conn->retbuf, conn->retlen);
     agent_cancel_query(conn);
-    return 0;
 }
 
 agent_pending_query *agent_query(
diff --git a/unix/uxnet.c b/unix/uxnet.c
index 79f4fbce..ddcd9228 100644
--- a/unix/uxnet.c
+++ b/unix/uxnet.c
@@ -1266,7 +1266,7 @@ static void sk_tcp_write_eof(Socket sock)
     uxsel_tell(s);
 }
 
-static int net_select_result(int fd, int event)
+static void net_select_result(int fd, int event)
 {
     int ret;
     char buf[20480];		       /* nice big buffer for plenty of speed */
@@ -1276,7 +1276,7 @@ static int net_select_result(int fd, int event)
     /* Find the Socket structure */
     s = find234(sktree, &fd, cmpforsearch);
     if (!s)
-	return 1;		       /* boggle */
+	return;		       /* boggle */
 
     noise_ultralight(event);
 
@@ -1292,9 +1292,9 @@ static int net_select_result(int fd, int event)
 	    ret = recv(s->s, buf, sizeof(buf), MSG_OOB);
 	    noise_ultralight(ret);
 	    if (ret <= 0) {
-                return plug_closing(s->plug,
-				    ret == 0 ? "Internal networking trouble" :
-				    strerror(errno), errno, 0);
+                plug_closing(s->plug,
+			     ret == 0 ? "Internal networking trouble" :
+			     strerror(errno), errno, 0);
 	    } else {
                 /*
                  * Receiving actual data on a socket means we can
@@ -1305,7 +1305,7 @@ static int net_select_result(int fd, int event)
                     sk_addr_free(s->addr);
                     s->addr = NULL;
                 }
-		return plug_receive(s->plug, 2, buf, ret);
+		plug_receive(s->plug, 2, buf, ret);
 	    }
 	    break;
 	}
@@ -1377,11 +1377,11 @@ static int net_select_result(int fd, int event)
 	    }
 	}
 	if (ret < 0) {
-            return plug_closing(s->plug, strerror(errno), errno, 0);
+            plug_closing(s->plug, strerror(errno), errno, 0);
 	} else if (0 == ret) {
             s->incomingeof = TRUE;     /* stop trying to read now */
             uxsel_tell(s);
-	    return plug_closing(s->plug, NULL, 0, 0);
+	    plug_closing(s->plug, NULL, 0, 0);
 	} else {
             /*
              * Receiving actual data on a socket means we can
@@ -1392,7 +1392,7 @@ static int net_select_result(int fd, int event)
                 sk_addr_free(s->addr);
                 s->addr = NULL;
             }
-	    return plug_receive(s->plug, atmark ? 0 : 1, buf, ret);
+	    plug_receive(s->plug, atmark ? 0 : 1, buf, ret);
 	}
 	break;
       case 2:			       /* writable */
@@ -1430,9 +1430,9 @@ static int net_select_result(int fd, int event)
                         err = try_connect(s);
                     }
                     if (err)
-                        return plug_closing(s->plug, strerror(err), err, 0);
+                        plug_closing(s->plug, strerror(err), err, 0);
                     if (!s->connected)
-                        return 0;      /* another async attempt in progress */
+                        return;      /* another async attempt in progress */
                 }
             }
 
@@ -1456,8 +1456,6 @@ static int net_select_result(int fd, int event)
 	}
 	break;
     }
-
-    return 1;
 }
 
 /*
diff --git a/unix/uxproxy.c b/unix/uxproxy.c
index 3df4cebe..d3a82fa4 100644
--- a/unix/uxproxy.c
+++ b/unix/uxproxy.c
@@ -33,7 +33,7 @@ struct Socket_localproxy_tag {
     enum { EOF_NO, EOF_PENDING, EOF_SENT } outgoingeof;
 };
 
-static int localproxy_select_result(int fd, int event);
+static void localproxy_select_result(int fd, int event);
 
 /*
  * Trees to look up the pipe fds in.
@@ -229,7 +229,7 @@ static const char * sk_localproxy_socket_error (Socket s)
     return ps->error;
 }
 
-static int localproxy_select_result(int fd, int event)
+static void localproxy_select_result(int fd, int event)
 {
     Local_Proxy_Socket s;
     char buf[20480];
@@ -238,7 +238,7 @@ static int localproxy_select_result(int fd, int event)
     if (!(s = find234(localproxy_by_fromfd, &fd, localproxy_fromfd_find)) &&
 	!(s = find234(localproxy_by_fromfd, &fd, localproxy_errfd_find)) &&
 	!(s = find234(localproxy_by_tofd, &fd, localproxy_tofd_find)) )
-	return 1;		       /* boggle */
+	return;		       /* boggle */
 
     if (event == 1) {
         if (fd == s->cmd_err) {
@@ -249,21 +249,18 @@ static int localproxy_select_result(int fd, int event)
             assert(fd == s->from_cmd);
             ret = read(fd, buf, sizeof(buf));
             if (ret < 0) {
-                return plug_closing(s->plug, strerror(errno), errno, 0);
+                plug_closing(s->plug, strerror(errno), errno, 0);
             } else if (ret == 0) {
-                return plug_closing(s->plug, NULL, 0, 0);
+                plug_closing(s->plug, NULL, 0, 0);
             } else {
-                return plug_receive(s->plug, 0, buf, ret);
+                plug_receive(s->plug, 0, buf, ret);
             }
         }
     } else if (event == 2) {
 	assert(fd == s->to_cmd);
 	if (localproxy_try_send(s))
 	    plug_sent(s->plug, bufchain_size(&s->pending_output_data));
-	return 1;
     }
-
-    return 1;
 }
 
 Socket platform_new_connection(SockAddr addr, const char *hostname,
diff --git a/unix/uxpty.c b/unix/uxpty.c
index 39f96f12..618fe9bd 100644
--- a/unix/uxpty.c
+++ b/unix/uxpty.c
@@ -572,7 +572,7 @@ void pty_pre_init(void)
 
 }
 
-int pty_real_select_result(Pty pty, int event, int status)
+void pty_real_select_result(Pty pty, int event, int status)
 {
     char buf[4096];
     int ret;
@@ -672,13 +672,10 @@ int pty_real_select_result(Pty pty, int event, int status)
 
 	notify_remote_exit(pty->frontend);
     }
-
-    return !finished;
 }
 
-int pty_select_result(int fd, int event)
+void pty_select_result(int fd, int event)
 {
-    int ret = TRUE;
     Pty pty;
 
     if (fd == pty_signal_pipe[0]) {
@@ -696,16 +693,14 @@ int pty_select_result(int fd, int event)
 	    pty = find234(ptys_by_pid, &pid, pty_find_by_pid);
 
 	    if (pty)
-		ret = ret && pty_real_select_result(pty, -1, status);
+		pty_real_select_result(pty, -1, status);
 	} while (pid > 0);
     } else {
 	pty = find234(ptys_by_fd, &fd, pty_find_by_fd);
 
 	if (pty)
-	    ret = ret && pty_real_select_result(pty, event, 0);
+	    pty_real_select_result(pty, event, 0);
     }
-
-    return ret;
 }
 
 static void pty_uxsel_setup(Pty pty)
diff --git a/unix/uxser.c b/unix/uxser.c
index 41beaf0e..e77f797a 100644
--- a/unix/uxser.c
+++ b/unix/uxser.c
@@ -56,7 +56,7 @@ static int serial_find_by_fd(void *av, void *bv)
 
 static tree234 *serial_by_fd = NULL;
 
-static int serial_select_result(int fd, int event);
+static void serial_select_result(int fd, int event);
 static void serial_uxsel_setup(Serial serial);
 static void serial_try_write(Serial serial);
 
@@ -366,7 +366,7 @@ static void serial_reconfig(void *handle, Conf *conf)
     serial_configure(serial, conf);
 }
 
-static int serial_select_result(int fd, int event)
+static void serial_select_result(int fd, int event)
 {
     Serial serial;
     char buf[4096];
@@ -376,7 +376,7 @@ static int serial_select_result(int fd, int event)
     serial = find234(serial_by_fd, &fd, serial_find_by_fd);
 
     if (!serial)
-	return 1;		       /* spurious event; keep going */
+	return;		       /* spurious event; keep going */
 
     if (event == 1) {
 	ret = read(serial->fd, buf, sizeof(buf));
@@ -391,11 +391,11 @@ static int serial_select_result(int fd, int event)
 	} else if (ret < 0) {
 #ifdef EAGAIN
 	    if (errno == EAGAIN)
-		return 1;	       /* spurious */
+		return;	       /* spurious */
 #endif
 #ifdef EWOULDBLOCK
 	    if (errno == EWOULDBLOCK)
-		return 1;	       /* spurious */
+		return;	       /* spurious */
 #endif
 	    perror("read serial port");
 	    exit(1);
@@ -417,8 +417,6 @@ static int serial_select_result(int fd, int event)
 
 	notify_remote_exit(serial->frontend);
     }
-
-    return !finished;
 }
 
 static void serial_uxsel_setup(Serial serial)