python - Program that either waits for user input or runs at defined intervals? -

i have program runs @ regular intervals. right program runs continuously, checking new files every 30 minutes:

def filechecker():     #check new files in directory , stuff  while true:     filechecker()     print '{} : sleeping...press ctrl+c stop.'.format(time.ctime())     time.sleep(1800) 

however, i'd user able come terminal , enter keystroke manually call filechecker() instead of either waiting program waking sleep or having relaunch program. possible do? tried @ using threading, couldn't figure out how wake computer sleep (don't have experience threading).

i know :

while true:     filechecker()     raw_input('press key continue') 

for full manual control, want have cake , eat too.

the solution provided clindseysmith introduces 1 more key press original question asking (at least, interpretation thereof). if want combine effect of 2 snippets of code in question, i.e., don't want have press ctrl+c calling file checker immediately, here's can do:

import time, threading  def filechecker():     #check new files in directory , stuff     print "{} : called!".format(time.ctime())  interval = 5 or 1800 t = none  def schedule():     filechecker()     global t     t = threading.timer(interval, schedule)     t.start()  try:     while true:         schedule()         print '{} : sleeping... press ctrl+c or enter!'.format(time.ctime())         = raw_input()         t.cancel() except keyboardinterrupt:     print '{} : stopped.'.format(time.ctime())     if t: t.cancel() 

the variable t holds id of thread scheduled next call file checker. pressing enter cancels t , reschedules. pressing ctrl-c cancels t , stops.