diff --git a/kitty/prewarm.py b/kitty/prewarm.py
index b37232090..08c2a131b 100644
--- a/kitty/prewarm.py
+++ b/kitty/prewarm.py
@@ -367,10 +367,6 @@ def fork(shm_address: str, free_non_child_resources: Callable[[], None]) -> Tupl
                 sys.stdin = sys.__stdin__
 
 
-class SocketClosed(Exception):
-    pass
-
-
 def verify_socket_creds(conn: socket.socket) -> bool:
     # needed as abstract unix sockets used on Linux have no permissions and
     # older BSDs ignore socket file permissions
@@ -385,6 +381,7 @@ class SocketChild:
         self.poll = poll
         self.addr = addr
         self.conn = conn
+        self.winsize = 8
         self.poll.register(self.conn.fileno(), select.POLLIN)
         self.input_buf = self.output_buf = b''
         self.fds: List[int] = []
@@ -395,6 +392,7 @@ class SocketChild:
         self.stdin = self.stdout = self.stderr = -1
         self.pid = -1
         self.closed = False
+        self.launch_msg_read = False
 
     def unregister_from_poll(self) -> None:
         if self.registered:
@@ -403,7 +401,21 @@ class SocketChild:
                 self.poll.unregister(self.conn.fileno())
             self.registered = False
 
-    def read(self) -> bool:
+    def read(self) -> None:
+        import fcntl
+        import termios
+        msg = self.conn.recv(io.DEFAULT_BUFFER_SIZE)
+        if not msg:
+            return
+        self.input_buf += msg
+        data = memoryview(self.input_buf)
+        while len(data) >= self.winsize:
+            record, data = data[:self.winsize], data[self.winsize:]
+            with open(os.open(self.tty_name, os.O_RDWR | os.O_CLOEXEC | os.O_NOCTTY, 0), 'rb') as f:
+                fcntl.ioctl(f.fileno(), termios.TIOCSWINSZ, record)
+        self.input_buf = bytes(data)
+
+    def read_launch_msg(self) -> bool:
         import array
         fds = array.array("i")   # Array of ints
         try:
@@ -421,13 +433,14 @@ class SocketChild:
                 fds.frombytes(cmsg_data[:len(cmsg_data) - (len(cmsg_data) % fds.itemsize)])
         self.fds += list(fds)
         if not msg:
-            raise SocketClosed('socket unexpectedly closed')
+            return False
         self.input_buf += msg
         while (idx := self.input_buf.find(b'\0')) > -1:
             line = self.input_buf[:idx].decode('utf-8')
             self.input_buf = self.input_buf[idx+1:]
             cmd, _, payload = line.partition(':')
             if cmd == 'finish':
+                self.launch_msg_read = True
                 for x in self.fds:
                     os.set_inheritable(x, x is not self.fds[0])
                     os.set_blocking(x, True)
@@ -454,6 +467,8 @@ class SocketChild:
                 self.stderr = int(payload)
             elif cmd == 'tty_name':
                 self.tty_name = payload
+            elif cmd == 'winsize':
+                self.winsize = int(payload)
 
         return False
 
@@ -506,6 +521,8 @@ class SocketChild:
         raise SystemExit(0)
 
     def handle_death(self, status: int) -> None:
+        if self.closed:
+            return
         if hasattr(os, 'waitstatus_to_exitcode'):
             status = os.waitstatus_to_exitcode(status)
             # negative numbers are signals usually and shells report these as
@@ -517,12 +534,10 @@ class SocketChild:
             self.conn.sendall(f'{status}'.encode('ascii'))
         except OSError as e:
             print_error(f'Failed to send exit status of socket child with error: {e}')
-        with suppress(OSError):
-            self.conn.shutdown(socket.SHUT_RDWR)
-        with suppress(OSError):
-            self.conn.close()
 
     def handle_creation(self) -> bool:
+        if self.closed:
+            return False
         try:
             self.conn.sendall(f'{self.pid}:'.encode('ascii'))
         except OSError as e:
@@ -535,7 +550,11 @@ class SocketChild:
             return
         self.unregister_from_poll()
         self.closed = True
-        self.conn.close()
+        if is_zygote:
+            with suppress(OSError):
+                self.conn.shutdown(socket.SHUT_RDWR)
+        with suppress(OSError):
+            self.conn.close()
         for x in self.fds:
             os.close(x)
         del self.fds[:]
@@ -694,6 +713,9 @@ def main(stdin_fd: int, stdout_fd: int, notify_child_death_fd: int, unix_socket:
                     if sc is not None:
                         try:
                             sc.handle_death(status)
+                        except Exception:
+                            import traceback
+                            traceback.print_exc()
                         finally:
                             remove_socket_child(sc)
                 else:
@@ -711,30 +733,32 @@ def main(stdin_fd: int, stdout_fd: int, notify_child_death_fd: int, unix_socket:
         sc = SocketChild(conn, addr, poll)
         socket_children[sc.conn.fileno()] = sc
 
-    def handle_socket_launch(fd: int, event: int) -> None:
+    def handle_socket_input(fd: int, event: int) -> None:
         scq = socket_children.get(q)
         if scq is None:
             return
         if event & select.POLLIN:
-            try:
-                if scq.read():
-                    scq.unregister_from_poll()
-                    scq.fork(free_non_child_resources)
-                    socket_pid_map[scq.pid] = scq
-                    scq.child_id = next(child_id_counter)
-            except SocketClosed:
-                if is_zygote:
-                    remove_socket_child(scq)
-            except OSError:
-                if is_zygote:
-                    remove_socket_child(scq)
-                    import traceback
-                    tb = traceback.format_exc()
-                    print_error(f'Failed to fork socket child with error: {tb}')
-                else:
-                    raise
+            if scq.launch_msg_read:
+                scq.read()
+            else:
+                try:
+                    if scq.read_launch_msg():
+                        scq.fork(free_non_child_resources)
+                        socket_pid_map[scq.pid] = scq
+                        scq.child_id = next(child_id_counter)
+                except OSError:
+                    if is_zygote:
+                        remove_socket_child(scq)
+                        import traceback
+                        tb = traceback.format_exc()
+                        print_error(f'Failed to fork socket child with error: {tb}')
+                    else:
+                        raise
         if is_zygote and (event & error_events):
-            remove_socket_child(scq)
+            if event & select.POLLHUP:
+                scq.unregister_from_poll()
+            else:
+                remove_socket_child(scq)
 
     keep_type_checker_happy = True
     try:
@@ -755,7 +779,7 @@ def main(stdin_fd: int, stdout_fd: int, notify_child_death_fd: int, unix_socket:
                 elif q == unix_socket.fileno():
                     handle_socket_client(event)
                 else:
-                    handle_socket_launch(q, event)
+                    handle_socket_input(q, event)
     except (KeyboardInterrupt, EOFError, BrokenPipeError):
         if is_zygote:
             raise SystemExit(1)
diff --git a/prewarm-launcher.c b/prewarm-launcher.c
index aeb81b572..dc3c0066e 100644
--- a/prewarm-launcher.c
+++ b/prewarm-launcher.c
@@ -124,6 +124,14 @@ safe_read(int fd, void *buf, size_t n) {
     return ret;
 }
 
+static ssize_t
+safe_send(int fd, void *buf, size_t n, int flags) {
+    ssize_t ret = 0;
+    while((ret = send(fd, buf, n, flags)) ==-1 && errno == EINTR);
+    return ret;
+}
+
+
 static ssize_t
 safe_write(int fd, void *buf, size_t n) {
     ssize_t ret = 0;
@@ -307,6 +315,8 @@ create_launch_msg(int argc, char *argv[]) {
 #define w(prefix, data) { if (!write_item_to_launch_msg(prefix, data)) return false; }
     static char buf[4*PATH_MAX];
     w("tty_name", child_tty_name);
+    snprintf(buf, sizeof(buf), "%zu", sizeof(self_winsize));
+    w("winsize", buf);
     if (getcwd(buf, sizeof(buf))) { w("cwd", buf); }
     for (int i = 0; i < argc; i++) w("argv", argv[i]);
     char **s = environ;
@@ -512,6 +522,40 @@ flush_data(void) {
     }
 }
 
+static char sosbuf[2 * sizeof(self_winsize)] = {0};
+static transfer_buf send_on_socket = {.buf=sosbuf};
+
+static void
+add_window_size_to_buffer(void) {
+    char *p;
+    if (send_on_socket.sz % sizeof(self_winsize)) {
+        // partial send
+        if (send_on_socket.sz > sizeof(self_winsize)) send_on_socket.sz -= sizeof(self_winsize); // replace second size
+        p = send_on_socket.buf + send_on_socket.sz;
+        send_on_socket.sz += sizeof(self_winsize);
+    } else {
+        // replace all sizes
+        p = send_on_socket.buf;
+        send_on_socket.sz = sizeof(self_winsize);
+    }
+    memcpy(p, &self_winsize, sizeof(self_winsize));
+}
+
+static bool
+send_over_socket(void) {
+    if (!send_on_socket.sz || socket_fd < 0) return true;
+    ssize_t n = safe_send(socket_fd, send_on_socket.buf, send_on_socket.sz, MSG_NOSIGNAL);
+    if (n < 0) return false;
+    if (n) {
+        if (n >= send_on_socket.sz) send_on_socket.sz = 0;
+        else {
+            send_on_socket.sz -= n;
+            memmove(send_on_socket.buf, send_on_socket.buf + n, send_on_socket.sz);
+        }
+    }
+    return true;
+}
+
 static void
 loop(void) {
 #define fail(s) { print_error(s, errno); return; }
@@ -523,15 +567,17 @@ loop(void) {
     nfds++;
 
     while (keep_going()) {
-        wf.self_ttyfd.want_read = to_child_tty.sz < IO_BUZ_SZ; wf.self_ttyfd.want_write = from_child_tty.sz > 0;
-        wf.child_master_fd.want_read = from_child_tty.sz < IO_BUZ_SZ; wf.child_master_fd.want_write = to_child_tty.sz > 0;
-        wf.socket_fd.want_write = launch_msg.iov_len > 0;
-
-        if (window_size_dirty && child_master_fd > -1 ) {
+        if (window_size_dirty) {
             if (!get_window_size()) fail("getting window size for self tty failed");
-            if (!safe_winsz(child_master_fd, TIOCSWINSZ, &self_winsize)) fail("setting window size on child pty failed");
+            // macOS barfs with ENOTTY if we try to use TIOCSWINSZ from this process, so send it to the zygote
+            /* if (!safe_winsz(child_master_fd, TIOCSWINSZ, &self_winsize)) fail("setting window size on child pty failed"); */
+            add_window_size_to_buffer();
             window_size_dirty = false;
         }
+        wf.self_ttyfd.want_read = to_child_tty.sz < IO_BUZ_SZ; wf.self_ttyfd.want_write = from_child_tty.sz > 0;
+        wf.child_master_fd.want_read = from_child_tty.sz < IO_BUZ_SZ; wf.child_master_fd.want_write = to_child_tty.sz > 0;
+        wf.socket_fd.want_write = launch_msg.iov_len > 0 || send_on_socket.sz > 0;
+
         FD_ZERO(&readable); FD_ZERO(&writable); FD_ZERO(&errorable);
 #define set(which) if (which > -1) { if (wf.which.want_read) { FD_SET(which, &readable); } if (wf.which.want_write) { FD_SET(which, &writable); } if (wf.which.want_error) { FD_SET(which, &errorable); } }
         set(self_ttyfd); set(child_master_fd); set(socket_fd); set(signal_read_fd);
@@ -553,7 +599,10 @@ loop(void) {
         if (signal_read_fd > -1 && FD_ISSET(signal_read_fd, &readable)) if (!read_signals()) fail("reading from signal fd failed");
 
         if (socket_fd > -1) {
-            if (FD_ISSET(socket_fd, &writable)) if (!send_launch_msg()) fail("sending launch message failed");
+            if (FD_ISSET(socket_fd, &writable)) {
+                if (launch_msg.iov_len > 0) { if (!send_launch_msg()) fail("sending launch message failed"); }
+                else if (send_on_socket.sz > 0) { if (!send_over_socket()) fail("sending on socket failed"); }
+            }
             if (FD_ISSET(socket_fd, &readable)) {
                 if (!read_child_data()) fail("reading information about child failed");
                 if (socket_fd < 0) { // hangup