Index: uspace/lib/posix/test/stdio.c
===================================================================
--- uspace/lib/posix/test/stdio.c	(revision 82d9087eea063af26837d04a2157c462f27708b0)
+++ uspace/lib/posix/test/stdio.c	(revision 3cdd876d0918f7f14a6d0e500a2f8a23bfdcb133)
@@ -47,5 +47,5 @@
 	    str_length("/tmp/tmp.")) == 0);
 
-	f = fopen(p, "w+");
+	f = fopen(p, "w+x");
 	PCUT_ASSERT_NOT_NULL(f);
 
@@ -66,5 +66,5 @@
 	    str_length("/tmp/tmp.")) == 0);
 
-	f = fopen(p, "w+");
+	f = fopen(p, "w+x");
 	PCUT_ASSERT_NOT_NULL(f);
 
@@ -85,5 +85,5 @@
 	    str_length(P_tmpdir "/tmp.")) == 0);
 
-	f = fopen(p, "w+");
+	f = fopen(p, "w+x");
 	PCUT_ASSERT_NOT_NULL(f);