Fix build with MSVC.
diff --git a/md2html/md2html.c b/md2html/md2html.c
index ddbcd7b..f8d955e 100644
--- a/md2html/md2html.c
+++ b/md2html/md2html.c
@@ -33,6 +33,10 @@
#include "cmdline.h"
#include "entity.h"
+#ifdef _WIN32
+ #define snprintf _snprintf
+#endif
+
/* Global options. */
static unsigned renderer_flags = 0;