diff --git a/test/systemtest/test_utils.py b/test/systemtest/test_utils.py
index 87f0565..8640bf2 100644
--- a/test/systemtest/test_utils.py
+++ b/test/systemtest/test_utils.py
@@ -9,6 +9,7 @@
 import logging
 import os
 import re
+import select
 import shlex
 import signal
 import subprocess
@@ -17,7 +18,6 @@
 
 class Process:
     """Utility class used to spawn an interact with processs.s"""
-
     def __init__(self,
                  cmd,
                  logdir,
@@ -80,14 +80,13 @@
 
         self._f_stdout = open(logfile_stdout, 'w')
         self._f_stderr = open(logfile_stderr, 'w')
-        self.proc = subprocess.Popen(
-            cmd,
-            cwd=self.cwd,
-            universal_newlines=True,
-            bufsize=1,
-            stdin=subprocess.PIPE,
-            stdout=self._f_stdout,
-            stderr=self._f_stderr)
+        self.proc = subprocess.Popen(cmd,
+                                     cwd=self.cwd,
+                                     universal_newlines=True,
+                                     bufsize=1,
+                                     stdin=subprocess.PIPE,
+                                     stdout=self._f_stdout,
+                                     stderr=self._f_stderr)
 
         self._f_stdout_r = open(logfile_stdout, 'r')
         self._f_stderr_r = open(logfile_stderr, 'r')
@@ -98,8 +97,8 @@
 
         # check if the string indicating a successful startup appears in the
         # the program output (STDOUT or STDERR)
-        init_done = self._find_in_output(
-            pattern=self.startup_done_expect, timeout=self.startup_timeout)
+        init_done = self.find_in_output(pattern=self.startup_done_expect,
+                                        timeout=self.startup_timeout)
 
         if init_done == None:
             raise subprocess.TimeoutExpired
@@ -144,9 +143,9 @@
         if pattern == None:
             return True
 
-        return self._find_in_output(pattern, timeout) != None
+        return self.find_in_output(pattern, timeout) != None
 
-    def _find_in_output(self, pattern, timeout):
+    def find_in_output(self, pattern, timeout):
         """Read STDOUT and STDERR to find an expected pattern.
 
         Both streams are reset to the start of the stream before searching.
@@ -169,7 +168,6 @@
         if timeout != None:
             t_end = time.time() + timeout
 
-
         # reset streams
         self._f_stdout_r.seek(0)
         self._f_stderr_r.seek(0)
@@ -217,3 +215,51 @@
                     pass
 
         return None
+
+
+def stream_fd_to_log(fd, logger, pattern, timeout=None):
+    """
+    Streams lines from the given fd to log until pattern matches.
+
+    Returns the match object derived from pattern.match(), or None if
+    the timeout expires.
+    """
+
+    deadline = None
+    if timeout != None:
+        deadline = time.monotonic() + timeout
+
+    os.set_blocking(fd, False)
+    line_of_output = b''
+    while True:
+        if deadline != None and time.monotonic() > deadline:
+            return None
+
+        if line_of_output.endswith(b'\n'):
+            line_of_output = b''
+
+        # select() on the fd so that we don't waste time reading when
+        # we wouldn't get anything out of it.
+        if deadline != None:
+            rlist, _, _ = select.select([fd], [], [],
+                                        deadline - time.monotonic())
+        else:
+            rlist, _, _ = select.select([fd], [], [])
+
+        if len(rlist) == 0:
+            continue
+
+        raw_bytes = os.read(fd, 1024)
+        lines = raw_bytes.splitlines(True)
+
+        for line in lines:
+            line_of_output += line
+            if not line_of_output.endswith(b'\n'):
+                break
+
+            logger.debug('fd#%d: %s' % (fd, line_of_output))
+            match = pattern.match(line_of_output.decode('utf-8'))
+            if match != None:
+              return match
+
+            line_of_output = b''