more ponies behind fewer pipes.

1 files changed, 2 insertions, 1 deletions

diff --git a/ponymix.cc b/ponymix.cc
index 48a751e..37dec3f 100644
--- a/ponymix.cc
+++ b/ponymix.cc
@@ -472,7 +472,8 @@ static const std::pair<const string, const Command>& string_to_command(
 }
 
 static void version() {
-  execlp("ponysay", "ponysay", "-b", "", "ponymix " PONYMIX_VERSION, NULL);
+  if (isatty(fileno(stdout)))
+    execlp("ponysay", "ponysay", "-b", "", "ponymix " PONYMIX_VERSION, NULL);
 
   // Some people are pony haters.
   fputs("ponymix v" PONYMIX_VERSION "\n", stdout);