+YAZ_EXPORT char *nmem_strdup (NMEM mem, const char *src);
+
+#if NMEM_DEBUG
+
+YAZ_EXPORT NMEM nmem_create_f(const char *file, int line);
+YAZ_EXPORT void nmem_destroy_f(const char *file, int line, NMEM n);
+#define nmem_create() nmem_create_f(__FILE__, __LINE__)
+#define nmem_destroy(x) nmem_destroy_f(__FILE__, __LINE__, (x))
+
+#else
+