[1.3.X] Fix #15880: Prevent "stalling" when running dev server in background by ignoring SIGTTOU for the duration of tcsetattr.

Backport of [16326] from trunk.

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.3.X@16327 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/utils/autoreload.py

@@ -28,7 +28,7 @@
 # OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-import os, sys, time
+import os, sys, time, signal
 
 try:
     import thread
@@ -78,7 +78,13 @@ def ensure_echo_on():
             attr_list = termios.tcgetattr(fd)
             if not attr_list[3] & termios.ECHO:
                 attr_list[3] |= termios.ECHO
+                if hasattr(signal, 'SIGTTOU'):
+                    old_handler = signal.signal(signal.SIGTTOU, signal.SIG_IGN)
+                else:
+                    old_handler = None
                 termios.tcsetattr(fd, termios.TCSANOW, attr_list)
+                if old_handler is not None:
+                    signal.signal(signal.SIGTTOU, old_handler)
 
 def reloader_thread():
     ensure_echo_on()