From: Pádraig Brady <P@draigBrady.com>
Date: Mon, 13 Jul 2026 16:50:21 +0000 (+0100)
Subject: tests: dd: ensure nocache flag does not fail with pipes
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=2653c5c5e2d2ee34a5ca6c6e83c9368a27b9a807;p=thirdparty%2Fcoreutils.git

tests: dd: ensure nocache flag does not fail with pipes

* tests/dd/nocache.sh: Whether fadvise() is called (uutils)
or avoided (GNU), ensure there is no failure when nocache
is only the ancillary operation being requested.

Link: https://github.com/coreutils/coreutils/pull/276
---

diff --git a/tests/dd/nocache.sh b/tests/dd/nocache.sh
index 405a7d12ca..154326e3e7 100755
--- a/tests/dd/nocache.sh
+++ b/tests/dd/nocache.sh
@@ -25,6 +25,10 @@ dd iflag=nocache oflag=nocache if=/dev/null of=/dev/null || fail=1
 # We should get an error for trying to process a pipe
 dd count=0 | returns_ 1 dd iflag=nocache count=0 || fail=1
 
+# We should not get an error unless count=0.  I.e., no error unless
+# dropping cache is the only operation being requested.
+dd count=0 | dd iflag=nocache oflag=nocache || fail=1
+
 # O_DIRECT is orthogonal to drop cache so mutually exclusive
 returns_ 1 dd iflag=nocache,direct if=/dev/null || fail=1