Oops, stop showbuildenv reading from stdin when run from a TTY.

David spotted the problem I introduced with 8374c3c.  Alter offset to
process any arguments, falling back to stdin if none.

diff --git a/tools/showbuildenv b/tools/showbuildenv
index 4645049..10c29bb 100755 (executable)
--- a/tools/showbuildenv
+++ b/tools/showbuildenv
@@ -14,7 +14,7 @@
 # It jumps through hoops with `|| true' despite not using `set -e'.
 
 offset () {
-    sed -e '/./s/^/    /'
+    sed -e '/./s/^/    /' "$@"
 }
 
 header () {