diff --git a/src/doFileSnapshot.cpp b/src/doFileSnapshot.cpp
index 0bda8ea6..6d0578e8 100644
--- a/src/doFileSnapshot.cpp
+++ b/src/doFileSnapshot.cpp
@@ -24,6 +24,8 @@
  */
 //-----------------------------------------------------------------------------
 
+#include <cstdlib>
+
 #include <iostream>
 #include <fstream>
 #include <stdexcept>