diff --git a/cpukit/shttpd/auth.c b/cpukit/shttpd/auth.c
index 5c9aec92ad..745f8ed709 100644
--- a/cpukit/shttpd/auth.c
+++ b/cpukit/shttpd/auth.c
@@ -10,6 +10,7 @@
 
 #include "defs.h"
 
+#include <unistd.h>
 #ifdef HAVE_STRINGS_H
 #include <strings.h>
 #endif
diff --git a/cpukit/shttpd/config.c b/cpukit/shttpd/config.c
index 92793d912c..e9240e549e 100644
--- a/cpukit/shttpd/config.c
+++ b/cpukit/shttpd/config.c
@@ -10,6 +10,8 @@
 
 #include "defs.h"
 
+#include <unistd.h>
+
 /*
  * Configuration parameters setters
  */
diff --git a/cpukit/shttpd/io_cgi.c b/cpukit/shttpd/io_cgi.c
index f7efb6423f..70ff2725fc 100644
--- a/cpukit/shttpd/io_cgi.c
+++ b/cpukit/shttpd/io_cgi.c
@@ -10,6 +10,8 @@
 
 #include "defs.h"
 
+#include <unistd.h>
+
 static int
 write_cgi(struct stream *stream, const void *buf, size_t len)
 {
diff --git a/cpukit/shttpd/io_file.c b/cpukit/shttpd/io_file.c
index d2b3fb66aa..fedc2df28c 100644
--- a/cpukit/shttpd/io_file.c
+++ b/cpukit/shttpd/io_file.c
@@ -10,6 +10,8 @@
 
 #include "defs.h"
 
+#include <unistd.h>
+
 static int
 write_file(struct stream *stream, const void *buf, size_t len)
 {
diff --git a/cpukit/shttpd/io_socket.c b/cpukit/shttpd/io_socket.c
index 9e2b73edc4..151419af51 100644
--- a/cpukit/shttpd/io_socket.c
+++ b/cpukit/shttpd/io_socket.c
@@ -10,6 +10,8 @@
 
 #include "defs.h"
 
+#include <unistd.h>
+
 static int
 read_socket(struct stream *stream, void *buf, size_t len)
 {
diff --git a/cpukit/shttpd/shttpd.c b/cpukit/shttpd/shttpd.c
index 29b8025aa9..66dc7fd846 100644
--- a/cpukit/shttpd/shttpd.c
+++ b/cpukit/shttpd/shttpd.c
@@ -15,6 +15,7 @@
 
 #include "defs.h"
 
+#include <unistd.h>
 #ifdef HAVE_STRINGS_H
 #include <strings.h>
 #endif