1 files changed, 15 insertions, 0 deletions
diff --git a/ext/ODBM_File/ODBM_File.xs b/ext/ODBM_File/ODBM_File.xs
index c1b405ff89..92b443ce99 100644
--- a/ext/ODBM_File/ODBM_File.xs
+++ b/ext/ODBM_File/ODBM_File.xs
@@ -13,6 +13,21 @@
 #  endif
 #endif
 
+#ifdef DBM_BUG_DUPLICATE_FREE 
+/*
+ * DBM on at least Ultrix and HPUX call dbmclose() from dbminit(),
+ * resulting in duplicate free() because dbmclose() does *not*
+ * check if it has already been called for this DBM.
+ * If some malloc/free calls have been done between dbmclose() and
+ * the next dbminit(), the memory might be used for something else when
+ * it is freed.
+ * Verified to work on ultrix4.3.  Probably will work on HP/UX.
+ * Set DBM_BUG_DUPLICATE_FREE in the extension hint file.
+ */
+/* Close the previous dbm, and fail to open a new dbm */
+#define dbmclose()	((void) dbminit("/tmp/x/y/z/z/y"))
+#endif
+
 #include <fcntl.h>
 
 typedef void* ODBM_File;