diff --git a/comedi_calibrate/save_cal.c b/comedi_calibrate/save_cal.c
index 60ee087..f7b3fb9 100644
--- a/comedi_calibrate/save_cal.c
+++ b/comedi_calibrate/save_cal.c
@@ -28,6 +28,7 @@ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 #include <stdlib.h>
 #include <assert.h>
 #include <time.h>
+#include <string.h>
 
 #include <comedilib.h>
 
diff --git a/demo/sv.c b/demo/sv.c
index ae51115..41814f8 100644
--- a/demo/sv.c
+++ b/demo/sv.c
@@ -17,6 +17,7 @@
 #include <errno.h>
 #include <getopt.h>
 #include <ctype.h>
+#include <stdlib.h>
 #include "examples.h"
 
 comedi_t *device;