diff -ur openjpeg-2.3.1.orig/src/lib/openjpip/imgsock_manager.c openjpeg-2.3.1/src/lib/openjpip/imgsock_manager.c
--- openjpeg-2.3.1.orig/src/lib/openjpip/imgsock_manager.c	2019-04-02 07:45:15.000000000 +0000
+++ openjpeg-2.3.1/src/lib/openjpip/imgsock_manager.c	2019-06-10 19:29:43.372398963 +0000
@@ -30,6 +30,10 @@
 
 #include <stdio.h>
 #include <string.h>
+#if defined(__sun)
+/* for strncasecmp() */
+# include <strings.h>
+#endif
 #include <stdlib.h>
 #include "imgsock_manager.h"
 #if _WIN32