diff --git a/lib/thread.h b/lib/thread.h
index 5a3bf7d..dafd438 100644
--- a/lib/thread.h
+++ b/lib/thread.h
@@ -45,6 +45,12 @@
 
 struct pqueue;
 
+/*
+ * Abstract it so we can use different methodologies to
+ * select on data.
+ */
+typedef fd_set thread_fd_set;
+
 /* Master of the theads. */
 struct thread_master
 {
@@ -56,9 +62,9 @@
   struct thread_list unuse;
   struct pqueue *background;
   int fd_limit;
-  fd_set readfd;
-  fd_set writefd;
-  fd_set exceptfd;
+  thread_fd_set readfd;
+  thread_fd_set writefd;
+  thread_fd_set exceptfd;
   unsigned long alloc;
 };