non_blocking sometimes fails unit tests.

[GoogleCodeExporter]

One out of many runs of check_io produced the following:

28/34 Testing: check_io
28/34 Test: check_io
Command: "/bin/nice" "./check_io" 
Directory: /home/sears/workspace/stasis/build/test/stasis
"check_io" start time: Apr 19 18:00 PDT
Output:
----------------------------------------------------------
io:
        io_memoryTest...io_memoryTest
Seed = 1271725238
Running concurrency test with 68259 values
pass
        io_fileTest...io_fileTest
pass
        io_pfileTest...Warning: There is a race condition between force()
and truncate() in file.c (This shouldn't matter in practice, as the logger
hasn't moved over to use file.c yet.
Seed = 1271725336
io_pfileTest
Seed = 1271725404
Running concurrency test with 92623 values
pass
        io_nonBlockingTest_file...io_nonBlockingTest
check_io: /home/sears/workspace/stasis/test/stasis/check_io.c:238:
load_handle: Assertion `*(int*)(r->buf) == t->values[val]' failed.
Seed = 1271725487
Warning: There is a race condition between force_range() and truncate() in
file.c (This shouldn't matter in practice, as the logger hasn't moved over
to use file.c yet.
----------------------------------------------------------
"check_io" end time: Apr 19 18:04 PDT
"check_io" time elapsed: 00:04:09
----------------------------------------------------------

This is low priority because there is no reason to enable non_blocking on
modern Linux systems.

Original issue reported on code.google.com by [email protected] on 20 Apr 2010 at 1:28