stdin_hello.py

import thread
import time

def hello(name=''):
    while 1:
        time.sleep(2)
        print "hello ", name

def main():
    thread.start_new_thread(hello, ('bob',))
    time.sleep(1)
    thread.start_new_thread(hello, ('alice',))
    while 1:
        name = raw_input('Please input your name:')
        if name.strip(): thread.start_new_thread(hello, (name,))

if __name__ == '__main__':
    main()