diff --git a/catalog.c b/catalog.c
index 880f9100..bea1418d 100644
--- a/catalog.c
+++ b/catalog.c
@@ -23,6 +23,8 @@
 #endif
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
+#elif defined (_WIN32)
+#include <io.h>
 #endif
 #ifdef HAVE_FCNTL_H
 #include <fcntl.h>
diff --git a/nanoftp.c b/nanoftp.c
index b52f9b64..2bfba853 100644
--- a/nanoftp.c
+++ b/nanoftp.c
@@ -23,6 +23,8 @@
 
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
+#elif defined (_WIN32)
+#include <io.h>
 #endif
 #ifdef HAVE_SYS_SOCKET_H
 #include <sys/socket.h>
diff --git a/nanohttp.c b/nanohttp.c
index d9619fdb..e014fe48 100644
--- a/nanohttp.c
+++ b/nanohttp.c
@@ -22,6 +22,8 @@
 
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
+#elif defined (_WIN32)
+#include <io.h>
 #endif
 #ifdef HAVE_SYS_SOCKET_H
 #include <sys/socket.h>
diff --git a/xzlib.c b/xzlib.c
index a07b3c88..33c27a26 100644
--- a/xzlib.c
+++ b/xzlib.c
@@ -22,6 +22,8 @@
 #endif
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
+#elif defined (_WIN32)
+#include <io.h>
 #endif
 #ifdef LIBXML_ZLIB_ENABLED
 #include <zlib.h>