diff -r 000000000000 -r 6474c204b198 python/psutil/examples/nettop.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/python/psutil/examples/nettop.py	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,144 @@
+#!/usr/bin/env python
+#
+# $Id: iotop.py 1160 2011-10-14 18:50:36Z g.rodola@gmail.com $
+#
+# Copyright (c) 2009, Giampaolo Rodola'. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""
+Shows real-time network statistics.
+
+Author: Giampaolo Rodola' <g.rodola@gmail.com>
+"""
+
+import sys
+import os
+if os.name != 'posix':
+    sys.exit('platform not supported')
+import curses
+import atexit
+import time
+
+import psutil
+
+
+# --- curses stuff
+def tear_down():
+    win.keypad(0)
+    curses.nocbreak()
+    curses.echo()
+    curses.endwin()
+
+win = curses.initscr()
+atexit.register(tear_down)
+curses.endwin()
+lineno = 0
+
+def print_line(line, highlight=False):
+    """A thin wrapper around curses's addstr()."""
+    global lineno
+    try:
+        if highlight:
+            line += " " * (win.getmaxyx()[1] - len(line))
+            win.addstr(lineno, 0, line, curses.A_REVERSE)
+        else:
+            win.addstr(lineno, 0, line, 0)
+    except curses.error:
+        lineno = 0
+        win.refresh()
+        raise
+    else:
+        lineno += 1
+# --- curses stuff
+
+
+def bytes2human(n):
+    """
+    >>> bytes2human(10000)
+    '9.8 K'
+    >>> bytes2human(100001221)
+    '95.4 M'
+    """
+    symbols = ('K', 'M', 'G', 'T', 'P', 'E', 'Z', 'Y')
+    prefix = {}
+    for i, s in enumerate(symbols):
+        prefix[s] = 1 << (i+1)*10
+    for s in reversed(symbols):
+        if n >= prefix[s]:
+            value = float(n) / prefix[s]
+            return '%.2f %s' % (value, s)
+    return '%.2f B' % (n)
+
+def poll(interval):
+    """Retrieve raw stats within an interval window."""
+    tot_before = psutil.net_io_counters()
+    pnic_before = psutil.net_io_counters(pernic=True)
+    # sleep some time
+    time.sleep(interval)
+    tot_after = psutil.net_io_counters()
+    pnic_after = psutil.net_io_counters(pernic=True)
+    return (tot_before, tot_after, pnic_before, pnic_after)
+
+
+def refresh_window(tot_before, tot_after, pnic_before, pnic_after):
+    """Print stats on screen."""
+    global lineno
+
+    # totals
+    print_line("total bytes:           sent: %-10s   received: %s" \
+          % (bytes2human(tot_after.bytes_sent),
+             bytes2human(tot_after.bytes_recv))
+    )
+    print_line("total packets:         sent: %-10s   received: %s" \
+          % (tot_after.packets_sent, tot_after.packets_recv)
+    )
+
+
+    # per-network interface details: let's sort network interfaces so
+    # that the ones which generated more traffic are shown first
+    print_line("")
+    nic_names = list(pnic_after.keys())
+    nic_names.sort(key=lambda x: sum(pnic_after[x]), reverse=True)
+    for name in nic_names:
+        stats_before = pnic_before[name]
+        stats_after = pnic_after[name]
+        templ = "%-15s %15s %15s"
+        print_line(templ % (name, "TOTAL", "PER-SEC"), highlight=True)
+        print_line(templ % (
+            "bytes-sent",
+            bytes2human(stats_after.bytes_sent),
+            bytes2human(stats_after.bytes_sent - stats_before.bytes_sent) + '/s',
+        ))
+        print_line(templ % (
+            "bytes-recv",
+            bytes2human(stats_after.bytes_recv),
+            bytes2human(stats_after.bytes_recv - stats_before.bytes_recv) + '/s',
+        ))
+        print_line(templ % (
+            "pkts-sent",
+            stats_after.packets_sent,
+            stats_after.packets_sent - stats_before.packets_sent,
+        ))
+        print_line(templ % (
+            "pkts-recv",
+            stats_after.packets_recv,
+            stats_after.packets_recv - stats_before.packets_recv,
+        ))
+        print_line("")
+    win.refresh()
+    lineno = 0
+
+
+def main():
+    try:
+        interval = 0
+        while 1:
+            args = poll(interval)
+            refresh_window(*args)
+            interval = 1
+    except (KeyboardInterrupt, SystemExit):
+        pass
+
+if __name__ == '__main__':
+    main()