Merge lp:~mbp/launchpad/882370-pidfile into lp:launchpad

[Martin Pool]

[r=lifeless][bug=882370] Make pidfile doctest more robust

make another test perhaps less likely to fail because of timing issues, and perhaps more likely to explain what went wrong if it did fail

bug 882370

[Robert Collins (lifeless)]

review: Approve

=== modified file 'lib/canonical/lazr/doc/pidfile.txt'
--- lib/canonical/lazr/doc/pidfile.txt	2008-09-23 14:35:10 +0000
+++ lib/canonical/lazr/doc/pidfile.txt	2011-10-27 04:52:27 +0000
@@ -71,6 +71,7 @@
 or SIGTERM, too. We'll demonstrate this with a couple of functions, because
 we'll need them again later.
 
+    >>> import errno
     >>> import time
     >>> subprocess_code = '''
     ... import time
@@ -92,13 +93,21 @@
     ...
     >>> def stop(pid, sig):
     ...     os.kill(pid, sig)
-    ...     for i in range(20):
+    ...     for i in range(300):
     ...         if not os.path.exists(pidfile_path('nuts')):
     ...             print 'Stopped successfully'
     ...             break
     ...         time.sleep(0.1)
     ...     else:
-    ...         print 'Error: pid file was not removed'
+    ...         try:
+    ...             # Is it still here at all?
+    ...             os.kill(pid, 0)
+    ...         except OSError, e:
+    ...             if e.errno == errno.ESRCH:
+    ...                 print 'Error: pid file was not removed'
+    ...             else: raise
+    ...         else:
+    ...             print 'Error: process did not exit'
     ...
 
 Here's our example.  We start, and then stop with SIGINT.