#!/usr/bin/env python
"""
to-mbox.py:  Insert line feeds to create mbox format

Usage:   ./to-mbox.py  infile outfile
"""
import sys

if len(sys.argv) != 3:
    print __doc__
    sys.exit()

out = open(sys.argv[2],"w")

start = True
for line in open(sys.argv[1]):
    if line.find("From ") == 0:
        if start:
            start = False
        else:
            out.write("\n")
        line = line.replace(" at ", "@")
    out.write(line)

out.close()

You can speed up this processes by configuring ssh to reuse connection to the same server if its has a connection already established.

This is a feature of OpenSSH, which I have tested on Snow Leopard and Ubuntu.

As per manual,

ControlMaster
Enables the sharing of multiple sessions over a single network connection. When set to “yes”, ssh(1) will listen for connections on a control socket specified using the ControlPath argument. Additional sessions can connect to this socket using the same ControlPath with ControlMaster set to “no” (the default). These sessions will try to reuse the master instance’s network connection rather than initiating new ones, but will fall back to connecting normally if the control socket does not exist, or is not listening.

In order to configure, create or edit ~/.ssh/config file and add following lines -

Host *
ControlMaster auto
ControlPath /tmp/%r@%h:%p

In order to test above, you can use -v while using ssh command. This will print debug information message while establishing a connection. While using ControlMaster you will notice that the there are lesser messages.

debug1: auto-mux: Trying existing master

If you don’t want to reuse existing connection you can use ssh with -S none which will create a new connection.