.

bigfile/_file_zodb.pyx

@@ -92,15 +92,16 @@ cdef public class _ZBigFile(BigFile) [object _ZBigFile, type _ZBigFile_Type]:
     # it is called from PyBigFile.fileh_open(mmap_overlay=True) and .zfile
     # should be already associaed with jar and have oid.
     def blkmapper(_ZBigFile zf):
+        cdef wcfs.PyConn pywconn
         if zf.wconn == nil:
             zconn = zf.zself._p_jar
             assert zconn is not None
             # XXX locking? or rely on that ZODB objects for must be used from under 1 thread only?
             zf.foid = u64(zf.zself._p_oid)
 
-            # XXX join zconn to wconn
+            # join zconn to wconn; link to wconn from _ZBigFile
             pywconn = pywconnOf(zconn)
-            zf.wconn = pywconn.XXX
+            zf.wconn = pywconn.wconn
 
 
 # functions that we give to virtmem bigfile_ops .mmap*