.

bigfile/_file_zodb.pyx

@@ -74,12 +74,11 @@ cdef public class _ZBigFile(BigFile) [object _ZBigFile, type _ZBigFile_Type]:
     def storeblk(self, blk, buf):   return self.zself.storeblk(blk, buf)
 
     # blkmmapper returns pycapsule with virtmem mmapper for the file.
-    #
-    # XXX
-    #
-    # it is called from PyBigFile.fileh_open(mmap_overlay=True) and .zfile
-    # should be already associated with jar and have oid.
     def blkmmapper(_ZBigFile zf):
+        # it is called from under PyBigFile.fileh_open(mmap_overlay=True) and
+        # .zfile should be already associated with jar and have oid.
+
+        # make sure that WCFS file handle corresponding to ZBigFile is opened.
         cdef wcfs.PyFileH pywfileh
         if zf.wfileh == nil:
             zconn = zf.zself._p_jar
@@ -94,13 +93,13 @@ cdef public class _ZBigFile(BigFile) [object _ZBigFile, type _ZBigFile_Type]:
         # zf is ready to serve mmap requests via .wfileh
         # return pycapsule with corresponding mmap methods.
         #
-        # the capsule is not bound to particula _ZBigFile object because
-        # .mmap_* methods receive BigFile* argument which they upcaset to _ZBigFile.
+        # the capsule is not bound to particular _ZBigFile object because
+        # .mmap_* methods receive BigFile* argument which they upcast to _ZBigFile.
         return _ZBigFile_mmap_pycapsule
 
 
 # _ZBigFile_mmap_pycapsule is pycapsule with functions that we give to
-# PyBigFile for virtmem .mmap* ops.
+# PyBigFile for ZBigFile virtmem .mmap* ops.
 cdef extern from "<wendelin/bigfile/file.h>" nogil:
     struct bigfile_ops:
         pass