--- fingerprint-gui-1.04/src/UserSettings.cpp
+++ fingerprint-gui-1.04/src/UserSettings.cpp
@@ -30,6 +30,7 @@
 
 #include <syslog.h>
 #include <stdlib.h>
+#include <unistd.h>
 #include <sys/mount.h>
 #include <errno.h>
 
--- fingerprint-gui-1.04/src/IdentifierGUI.cpp
+++ fingerprint-gui-1.04/src/IdentifierGUI.cpp
@@ -25,6 +25,7 @@
 
 #include <string>
 #include <iostream>
+#include <unistd.h>
 #include "IdentifierGUI.h"
 
 #define KEEP_ON_TOP \
--- fingerprint-gui-1.04/src/FingerprintPAM.cpp
+++ fingerprint-gui-1.04/src/FingerprintPAM.cpp
@@ -37,6 +37,7 @@
 #include <errno.h>
 #include <pwd.h>
 #include <string>
+#include <unistd.h>
 
 #include "../include/Globals.h"
 
--- fingerprint-gui-1.04/src/PluginDialog.cpp
+++ fingerprint-gui-1.04/src/PluginDialog.cpp
@@ -25,6 +25,7 @@
 
 #include <sys/poll.h>
 #include <string>
+#include <unistd.h>
 #include <qt4/QtCore/qthread.h>
 
 #include "../include/PluginDialog.h"
--- fingerprint-gui-1.04/src/PamGUI.cpp
+++ fingerprint-gui-1.04/src/PamGUI.cpp
@@ -23,6 +23,7 @@
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include <unistd.h>
 #include "PamGUI.h"
 #include "FingerprintHelper.h"
 
--- fingerprint-gui-1.04/src/PamNonGUI.cpp
+++ fingerprint-gui-1.04/src/PamNonGUI.cpp
@@ -23,6 +23,7 @@
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include <unistd.h>
 #include "PamNonGUI.h"
 #include "FingerprintHelper.h"
 
--- fingerprint-gui-1.04/src/FingerprintPlugin.cpp
+++ fingerprint-gui-1.04/src/FingerprintPlugin.cpp
@@ -25,6 +25,7 @@
 
 #include <syslog.h>
 #include <string>
+#include <unistd.h>
 #include <qt4/QtGui/qwidget.h>
 
 #include "PluginDialog.h"