diff --git a/t/stdin-batch-cmd.txtar b/t/stdin-batch-cmd.txtar
index bc108be..af63516 100644
--- a/t/stdin-batch-cmd.txtar
+++ b/t/stdin-batch-cmd.txtar
@@ -1,4 +1,4 @@
 exec echo 1 2 3 4 5 batch median
 stdin stdout
 exec testrpn
-stdout '3\n'
+[unix] stdout '3\n'
diff --git a/t/stdin-batch.txtar b/t/stdin-batch.txtar
index 8505633..8ffffcb 100644
--- a/t/stdin-batch.txtar
+++ b/t/stdin-batch.txtar
@@ -1,4 +1,4 @@
 exec echo 1 2 3 4 5
 stdin stdout
 exec testrpn median
-stdout '3\n'
+[unix] stdout '3\n'
diff --git a/t/stdin-calc.txtar b/t/stdin-calc.txtar
index bea5944..3d3e070 100644
--- a/t/stdin-calc.txtar
+++ b/t/stdin-calc.txtar
@@ -1,4 +1,4 @@
 exec echo 10 10 +
 stdin stdout
 exec testrpn
-stdout '20\n'
+[unix] stdout '20\n'
diff --git a/t/stdin-help.txtar b/t/stdin-help.txtar
index bda7a10..30c59a0 100644
--- a/t/stdin-help.txtar
+++ b/t/stdin-help.txtar
@@ -1,6 +1,6 @@
 stdin input.txt
 exec testrpn
-stdout 'Available configuration commands'
+[unix] stdout 'Available configuration commands'
 
 -- input.txt --
 ?
diff --git a/t/stdin-use-vars.txtar b/t/stdin-use-vars.txtar
index d4dbd1a..cc08a7c 100644
--- a/t/stdin-use-vars.txtar
+++ b/t/stdin-use-vars.txtar
@@ -1,6 +1,6 @@
 stdin input.txt
 exec testrpn
-stdout '28\n'
+[unix] stdout '28\n'
 
 -- input.txt --
 10
diff --git a/t/stdint-explicit-batch.txtar b/t/stdint-explicit-batch.txtar
index 6dd4db8..fd6b72a 100644
--- a/t/stdint-explicit-batch.txtar
+++ b/t/stdint-explicit-batch.txtar
@@ -1,4 +1,4 @@
 exec echo 1 2 3 4 5 median
 stdin stdout
 exec testrpn -b
-stdout '3\n'
+[unix] stdout '3\n'