diff --git a/localtime.c b/localtime.c
index 13f54de..7ea3fe0 100644
--- a/localtime.c
+++ b/localtime.c
@@ -259,6 +259,13 @@ register struct state * const	sp;
 		return -1;
 	{
 		register int	doaccess;
+		/*
+		** Section 4.9.1 of the C standard says that
+		** "FILENAME_MAX expands to an integral constant expression
+		** that is the sie needed for an array of char large enough
+		** to hold the longest file name string that the implementation
+		** guarantees can be opened."
+		*/
 		char		fullname[FILENAME_MAX + 1];
 
 		if (name[0] == ':')