diff --unified '--color=auto' -r netcdf-c-4.7.4.orig/ncdump/ncvalidator.c netcdf-c-4.7.4/ncdump/ncvalidator.c
--- netcdf-c-4.7.4.orig/ncdump/ncvalidator.c	2020-03-27 21:03:36.000000000 +0530
+++ netcdf-c-4.7.4/ncdump/ncvalidator.c	2021-05-02 20:51:53.185118600 +0530
@@ -73,12 +73,10 @@
 #include <unistd.h>     /* read() getopt() */
 #endif
 
-#ifdef _WIN32
+#ifdef _MSC_VER
 #include <io.h>
-#define snprintf _snprintf
 #include "XGetopt.h"
-int opterr;
-int optind;
+#define snprintf _snprintf
 #endif
 
 #define X_ALIGN         4
diff --unified '--color=auto' -r netcdf-c-4.7.4.orig/ncdump/ocprint.c netcdf-c-4.7.4/ncdump/ocprint.c
--- netcdf-c-4.7.4.orig/ncdump/ocprint.c	2020-03-27 21:03:36.000000000 +0530
+++ netcdf-c-4.7.4/ncdump/ocprint.c	2021-05-02 20:49:16.023788600 +0530
@@ -29,6 +29,7 @@
 
 #include "oc.h"
 #include "ocx.h"
+#include "ocdebug.h"
 
 #ifdef _MSC_VER
 #include "XGetopt.h"
@@ -56,8 +57,6 @@
 /*Mnemonic*/
 #define TOPLEVEL 1
 
-int ocdebug;
-
 static OCerror ocstat;
 static OClink glink;