tests: dd/reblock: avoid occasional failure

* tests/dd/reblock: Sleep longer to avoid a race condition.
Reported by Bob Proulx.

diff --git a/tests/dd/reblock b/tests/dd/reblock
index 542529a71458341639cba42af7def87dff039dbb..ef9e0361308f8a8863a1f6e2fa2f74a90e1afef9 100755 (executable)
--- a/tests/dd/reblock
+++ b/tests/dd/reblock
@@ -44,7 +44,10 @@ sed 's/,.*//' err > k && mv k err
 compare err exp-reblock || fail=1
 
 # Demonstrate that bs=N supersedes even following ibs= and obs= settings.
-(echo x; sleep .1; echo y) | dd bs=3 ibs=1 obs=1 > out 2> err || fail=1
+# Choosing a delay of 0.1 would result in an occasional lost race where
+# the consumer's first read would consume 3 bytes rather than the expected 2.
+# Not wanting to sleep a full second, I'll raise that to 0.3.
+(printf ab; sleep .3; printf cd) | dd bs=3 ibs=1 obs=1 > out 2> err || fail=1
 sed 's/,.*//' err > k && mv k err
 compare err exp-no-reblock || fail=1