- * Returns true if the two file descriptors passed in can be determined to
- * reference the same file description, false otherwise
+ * Try to determine if two file descriptors reference the same file description
+ *
+ * Return values:
+ * - 0: They reference the same file description
+ * - > 0: They do not reference the same file description
+ * - < 0: Unable to determine whether they reference the same file description