Windows: Fix warning on info

Signed-off-by: John Howard <jhoward@microsoft.com>

fileutils/fileutils_unix.go

@@ -0,0 +1,22 @@
+// +build linux freebsd
+
+package fileutils
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+
+	"github.com/Sirupsen/logrus"
+)
+
+// GetTotalUsedFds Returns the number of used File Descriptors by
+// reading it via /proc filesystem.
+func GetTotalUsedFds() int {
+	if fds, err := ioutil.ReadDir(fmt.Sprintf("/proc/%d/fd", os.Getpid())); err != nil {
+		logrus.Errorf("Error opening /proc/%d/fd: %s", os.Getpid(), err)
+	} else {
+		return len(fds)
+	}
+	return -1
+}