#! /usr/bin/env python

# Print From and Subject of messages in $MAIL.

# Extension to multiple mailboxes and other bells & whistles are left

# as exercises for the reader.

import sys, os

# Open mailbox file.  Exits with exception when this fails.

try:

    mailbox = os.environ['MAIL']

except (AttributeError, KeyError):

    sys.stderr.write('No environment variable $MAIL\n')

    sys.exit(2)

try:

    mail = open(mailbox)

except IOError:

    sys.exit('Cannot open mailbox file: ' + mailbox)

while 1:

    line = mail.readline()

    if not line:

        break # EOF

    if line.startswith('From '):

        # Start of message found

        print line[:-1],

        while 1:

            line = mail.readline()

            if not line or line == '\n':

                break

            if line.startswith('Subject: '):

                print repr(line[9:-1]),

        print