Python 'tail' implementation

#!/usr/bin/pythonimport time,sysif len(sys.argv) > 1:	filename = sys.argv[1]else:	print "Must specify a filename!"	sys.exit()try:	f = open(filename)except:	print "Could not open %s for reading!" % filename	sys.exit()readBuffer = ''try:	while True:		readBuffer += f.read()		lastNewline = readBuffer.rfind('\n')		outputbuffer = readBuffer[:lastNewline].split('\n')		for line in outputbuffer:			if len(line)>0: print line		readBuffer = readBuffer[lastNewline+1:]		time.sleep(1)except KeyboardInterrupt:	print	print "** Received SIGINT - exiting **"	sys.exit()