1 files changed, 1 insertions, 1 deletions
diff --git a/ledger.h b/ledger.h
index e645860a..6c11fa5a 100644
--- a/ledger.h
+++ b/ledger.h
@@ -229,7 +229,7 @@ unsigned int parse_textual_journal(std::istream& in,
 				   journal_t *	 ledger,
 				   account_t *	 master = NULL);
 
-extern unsigned long binary_magic_number;
+extern const unsigned long binary_magic_number;
 
 unsigned int read_binary_journal(std::istream&	in,
 				 journal_t *	journal,