Index: main/parallel/src/pserver.cc
===================================================================
--- main/parallel/src/pserver.cc	(revision 10799)
+++ main/parallel/src/pserver.cc	(working copy)
@@ -35,6 +35,10 @@
 #include <netdb.h>
 #include <netinet/in.h> // reported necessary for FreeBSD-8
 
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
 #include "sock-stream.h"
 
 #include "config.h"
Index: main/parallel/src/connect.cc
===================================================================
--- main/parallel/src/connect.cc	(revision 10799)
+++ main/parallel/src/connect.cc	(working copy)
@@ -30,6 +30,10 @@
 #include <netdb.h>
 #include <netinet/in.h> // reported necessary for FreeBSD-8
 
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
 #include "sock-stream.h"
 
 static
Index: main/parallel/src/send.cc
===================================================================
--- main/parallel/src/send.cc	(revision 10799)
+++ main/parallel/src/send.cc	(working copy)
@@ -26,6 +26,9 @@
 #include <netinet/in.h>
 #include <netdb.h>
 
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
 
 DEFUN_DLD (send, args, , "send (X, sockets)\n\
 \n\
Index: main/parallel/src/recv.cc
===================================================================
--- main/parallel/src/recv.cc	(revision 10799)
+++ main/parallel/src/recv.cc	(working copy)
@@ -27,6 +27,9 @@
 #include <netinet/in.h>
 #include <netdb.h>
 
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
 
 DEFUN_DLD (recv, args, nargout, "recv (socket)\n\
 \n\