Add simple ExecPipe() to be used with filesystem format work

pkgs/utils/execpipe_test.go

@@ -0,0 +1,34 @@
+// !build linux,amd64
+
+package utils
+
+import (
+	. "gopkg.in/check.v1"
+	"os/exec"
+	"testing"
+)
+
+type MySuite struct{}
+
+var _ = Suite(&MySuite{})
+
+func Test(t *testing.T) { TestingT(t) }
+
+func (s *MySuite) TestPiping(c *C) {
+	// Collect directories from the command-line
+	dirs := []string{"."}
+
+	// Run the command on each directory
+	for _, dir := range dirs {
+		// find $DIR -type f # Find all files
+		ls := exec.Command("ls", dir, "-l")
+
+		// | sort -t. -k2 # Sort by file extension
+		sort := exec.Command("sort", "-t.", "-k2")
+
+		// Run
+		output, err := ExecPipe(ls, sort)
+		c.Assert(err, IsNil)
+		c.Assert(len(output), Not(Equals), 0)
+	}
+}