diff --git a/rdagent/utils/env.py b/rdagent/utils/env.py
index 178ca20e..dd4a8e1e 100644
--- a/rdagent/utils/env.py
+++ b/rdagent/utils/env.py
@@ -440,15 +440,18 @@ class LocalEnv(Env[ASpecificLocalConf]):
             for fd, event in events:
                 if event & select.POLLIN:
                     if fd == stdout_fd:
-                        output = process.stdout.readline()
-                        if output:
+                        while True:
+                            output = process.stdout.readline()
+                            if output == "":
+                                break
                             Console().print(output.strip(), markup=False)
                             combined_output += output
                     elif fd == stderr_fd:
-                        chunk = os.read(stderr_fd, 4096)
-                        if chunk:
-                            error = chunk.decode(errors="replace")
-                            Console().print(error, end="", markup=False)
+                        while True:
+                            error = process.stderr.readline()
+                            if error == "":
+                                break
+                            Console().print(error.strip(), markup=False)
                             combined_output += error
 
         # Capture any final output