diff --git a/kitty/child.py b/kitty/child.py
index dbfc5f221..7f4e998ad 100644
--- a/kitty/child.py
+++ b/kitty/child.py
@@ -252,6 +252,7 @@ class Child:
         env['KITTY_PID'] = getpid()
         if not self.is_prewarmed:
             env['KITTY_PREWARM_SOCKET'] = fast_data_types.get_boss().prewarm.socket_env_var()
+            env['KITTY_PREWARM_SOCKET_REAL_TTY'] = '0' * 32
         if self.cwd:
             # needed in case cwd is a symlink, in which case shells
             # can use it to display the current directory name rather
@@ -457,7 +458,12 @@ class Child:
         import termios
         if self.child_fd is None:
             return False
-        t = termios.tcgetattr(self.child_fd)
+        tty_name = self.foreground_environ.get('KITTY_PREWARM_SOCKET_REAL_TTY')
+        if tty_name and tty_name.startswith('/'):
+            with open(os.open(tty_name, os.O_RDWR | os.O_CLOEXEC | os.O_NOCTTY, 0)) as real_tty:
+                t = termios.tcgetattr(real_tty.fileno())
+        else:
+            t = termios.tcgetattr(self.child_fd)
         if not t[3] & termios.ISIG:
             return False
         cc = t[-1]
diff --git a/kitty_tests/prewarm.py b/kitty_tests/prewarm.py
index 416336b26..45c0442d1 100644
--- a/kitty_tests/prewarm.py
+++ b/kitty_tests/prewarm.py
@@ -65,7 +65,13 @@ def socket_child_main(exit_code=0, initial_print=''):
         if p is None:
             return
         env = os.environ.copy()
-        env.update({'TEST_ENV_PASS': 'xyz', 'KITTY_PREWARM_SOCKET': p.socket_env_var(), 'TERM': 'xterm-kitty', 'TERMINFO': terminfo_dir})
+        env.update({
+            'TEST_ENV_PASS': 'xyz',
+            'KITTY_PREWARM_SOCKET': p.socket_env_var(),
+            'KITTY_PREWARM_SOCKET_REAL_TTY': '0' * 32,
+            'TERM': 'xterm-kitty',
+            'TERMINFO': terminfo_dir
+        })
         cols = 117
 
         def wait_for_death(exit_code, timeout=5):
@@ -120,7 +126,7 @@ def socket_child_main(exit_code=0, initial_print=''):
                 argv=[kitty_exe(), '+runpy', src + 'socket_child_main(initial_print="child ready:")'], cols=cols, env=env, cwd=cwd)
             pty.wait_till(lambda: 'child ready:' in pty.screen_contents())
             from kitty.child import environ_of_process
-            self.assertTrue(environ_of_process(pty.child_pid).get('KITTY_PWPR'))
+            self.assertIn('/', environ_of_process(pty.child_pid).get('KITTY_PREWARM_SOCKET_REAL_TTY'))
             os.close(pty.master_fd)
 
         with self.subTest(msg='test passing of data via cwd, env vars and stdin/stdout redirection'):
diff --git a/prewarm-launcher.c b/prewarm-launcher.c
index 396977812..bc822e228 100644
--- a/prewarm-launcher.c
+++ b/prewarm-launcher.c
@@ -699,8 +699,8 @@ use_prewarmed_process(int argc, char *argv[], char *envp[]) {
 #undef fail
 
     while (*envp) {
-        if (strncmp(*envp, "KITTY_PREWARM_SOCKET=", 2) == 0) {
-            sprintf(*envp,  "KITTY_PWPR=%s", child_tty_name);
+        if (strncmp(*envp, "KITTY_PREWARM_SOCKET_REAL_TTY=", 2) == 0) {
+            sprintf(*envp,  "KITTY_PREWARM_SOCKET_REAL_TTY=%s", child_tty_name);
         }
         envp++;
     }