diff --git a/src/filesys.cpp b/src/filesys.cpp
index 99a0a6ef8..860168460 100644
--- a/src/filesys.cpp
+++ b/src/filesys.cpp
@@ -171,6 +171,7 @@ bool RecursiveDelete(std::string path)
 #include <errno.h>
 #include <sys/stat.h>
 #include <sys/wait.h>
+#include <unistd.h>
 
 std::vector<DirListNode> GetDirListing(std::string pathstring)
 {