diff --git a/android_build_server_helper.py b/android_build_server_helper.py
index e71ab9867..a75ce0ce8 100644
--- a/android_build_server_helper.py
+++ b/android_build_server_helper.py
@@ -50,15 +50,18 @@ def _start_server(local_dev_server_path):
 
 def _set_tty_env():
     stdout_name = os.readlink('/proc/self/fd/1')
-    os.environ.setdefault("AUTONINJA_STDOUT_NAME", stdout_name)
+    # Anonymous pipes can't be opened. These look like "pipe:[394765110]".
+    ret = os.path.exists(stdout_name)
+    if ret:
+        os.environ.setdefault("AUTONINJA_STDOUT_NAME", stdout_name)
+    return ret
 
 
 @contextlib.contextmanager
 def build_server_context(build_id, use_android_build_server=False):
-    if not use_android_build_server:
+    if not use_android_build_server or not _set_tty_env():
         yield
         return
-    _set_tty_env()
     server_path = _get_server_path()
     _start_server(server_path)
     # Tell the build server about us.