New submission from Giampaolo Rodola': This is based on progress made in issue 13564 and aims to provide a new sendfile() method for the socket class taking advantage of high-performance "zero-copy" os.sendfile() available on most POSIX platforms. A wrapper on top of os.sendfile() appears to be convenient because getting everything right is a bit tricky. Also we can avoid code duplication in case we want to add sendfile() support to ftplib (issue 13564) and httplib.
=== THE API === Attached is a draft patch proposing an API which: - uses os.sendfile() whenever available and usable (a mmap-like file is required) - if not falls back on using plain socket.sendall() - returns a tuple of two elements which indicates whether sendfile() was used and an exception instance in case it wasn't on account of an internal error, if any - does not support non-blocking sockets (will raise ValueError) === ALTERNATE API === 1) In case the transfer is interrupted halfway because of an error the user has no clue on how many bytes were sent (and file.tell() won't tell =)). As such it probably makes sense to provide a custom socket.SendfileError exception encapsulating the original exception and the bytes sent as arguments. 2) For the same reason the returned tuple should probably include the number of bytes transmitted. === WINDOWS SUPPORT === Further development may include Windows support by using TransmitFile (http://msdn.microsoft.com/en-us/library/windows/desktop/ms740565(v=vs.85).aspx). Once we agree on an API I might start looking into Windows code (which appears to be quite tricky btw). Any feedback is very welcome. ---------- components: Library (Lib) files: socket-sendfile.patch keywords: needs review, patch messages: 185292 nosy: giampaolo.rodola priority: normal severity: normal status: open title: socket.sendfile() type: enhancement versions: Python 3.4 Added file: http://bugs.python.org/file29583/socket-sendfile.patch _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue17552> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
