ENVELOPE *mutt_read_rfc822_header (FILE *, HEADER *, short, short);
HEADER *mutt_dup_header (HEADER *);
+int mutt_cmp_header (const HEADER*, const HEADER*);
+int mutt_cmp_addr (const ADDRESS * a, const ADDRESS * b);
+int mutt_cmp_list (const LIST * a, const LIST * b);
+int mutt_cmp_env (const ENVELOPE * e1, const ENVELOPE * e2);
+int mutt_cmp_param (const PARAMETER * p1, const PARAMETER * p2);
+int mutt_cmp_body (const BODY * b1, const BODY * b2);
+
#if USE_HCACHE
void *mutt_hcache_open (const char *path, const char *folder);
void mutt_hcache_close (void *db);