Moshe Zadka <mzadka@geocities.com>:

Document new method in shutil (copyfileobj).
Minor clarification by Fred.

Doc/lib/libshutil.tex

@@ -23,6 +23,15 @@ file type and creator codes will not be correct.
   it will be replaced, otherwise it will be created.
 \end{funcdesc}
 
+\begin{funcdesc}{copyfileobj}{fsrc, fdst\optional{, length}}
+  Copy the contents of the file-like object \var{fsrc} to the
+  file-like object \var{fdst}.  The integer \var{length}, if given,
+  is the buffer size. In particular, a negative \var{length} value
+  means to copy the data without looping over the source data in
+  chunks; by default the data is read in chunks to avoid uncontrolled
+  memory consumption.
+\end{funcdesc}
+
 \begin{funcdesc}{copymode}{src, dst}
   Copy the permission bits from \var{src} to \var{dst}.  The file
   contents, owner, and group are unaffected.