Question

I’m running a function which evaluates commands passed in using stdin and another function which runs a bunch of jobs. I need to make the latter function sleep at regular intervals but that seems to be blocking the stdin. Any advice on how to resolve this would be appreciated.

The source code for the functions is

def runJobs(comps, jobQueue, numRunning, limit, lock):
  while len(jobQueue) >= 0:
      print(len(jobQueue));
      if len(jobQueue) > 0:
          comp, tasks = find_computer(comps, 0);
            #do something
        time.sleep(5);

def manageStdin():
    print "Global Stdin Begins Now"
    for line in fileinput.input():
        try:
            print(eval(line));
        except Exception, e:
            print e;

–Thanks

Answer 1

Use a single thread:

import time
import select
import logging
import sys

def stdinWait(interval):
    start = time.time()
    while True:
        time_left = interval - (time.time() - start)
        if time_left <= 0:
            break
        r, w, x = select.select([sys.stdin], [], [], time_left)
        if r:
            line = r[0].readline()
            try:
                print(eval(line));
            except Exception, e:
                logging.exception(e)

def runJobs(comps, jobQueue, numRunning, limit, lock):
  while len(jobQueue) >= 0:
      print(len(jobQueue));
      if len(jobQueue) > 0:
          comp, tasks = find_computer(comps, 0);
          #do something
          stdinWait(5) # wait 5 seconds while watching stdin