--- a/photosyst.c	2020-12-25 13:13:46.569591017 +0000
+++ b/photosyst.c	2020-12-25 13:13:52.399619155 +0000
@@ -165,6 +165,7 @@
 #include <dirent.h>
 #include <sys/ioctl.h>
 #include <sys/sysmacros.h>
+#include <limits.h>
 
 #define SCALINGMAXCPU	8	// threshold for scaling info per CPU