How to use thread on just one line of python, not for all the script

Question

I need to know if there is a way I can just use multithreading in a single line, rather than the full program.

That is, I want to run the program as a single thread, but in the middle of it I want one particular line to be multithreaded. I want to multithread something like this:

br.open("http://www.google.com.pk/search?q="+str(m))

So, basically I want to open all the links (m can assume 50 distinct values), and I don't want to open them one after the other. I want to open all 50 at once! If I open them one by one, it slows the process down and I want to avoid that.

Just as a general comment, unrelated to _how_ to do this: Each of those `open` calls sends an HTTP request, and you should be careful about how many requests you send to the server (especially, Google) at once. They may block you if you do a lot of this without proper breaks / sleeps in between. — jogojapan, Jun 19 '12 at 07:42
Also, opening 50 threads at once doesn't necessarily make things faster. Anyway, here's some inspiration: [link](http://www.ibm.com/developerworks/aix/library/au-threadingpython/) — phipsgabler, Jun 19 '12 at 07:44
@ jedwards I have Core i7 2600k - @ phg As for the threading it will open 50 links once not like sequence wise - and that sequence wise makes it slower because when I open it once it takes 2 -4 sec to load the page - — Hoyo, Jun 19 '12 at 07:58

score 3 · Answer 1 · answered Jun 19 '12 at 07:50

You want to look at the threading.Thread class.

import threading

def worker():
    """thread worker function"""
    print 'Worker'
    return

threads = []
for i in range(5):
    t = threading.Thread(target=worker)
    threads.append(t)
    t.start()

If you are doing multiple HTTP requests you may also want to look at queue.Queue You would then queue up multiple http requests. Here is a nice example of that in action.

mhawke · Answer 2 · 2012-06-19T08:01:20.257

You are after asynchronous communications. I haven't tried it myself, but take a look at grequests. It used to be part of the requests library, but has been factored out. Usage (from their github page) seems very easy:

import grequests

urls = [
    'http://www.heroku.com',
    'http://tablib.org',
    'http://httpbin.org',
    'http://python-requests.org',
    'http://kennethreitz.com'
]
rs = (grequests.get(u) for u in urls)
grequests.map(rs)

If you want to keep within the Python standard library, you might take a look at the asyncore module.

Also, another alternative is Twisted. It might be overkill for your requirements, and the learning curve is notoriously steep.

score 0 · Answer 3 · answered Feb 17 '18 at 04:22

I would here be actually trying to answer the original question asked by the OP, I don't recommend this code due to obvious readability issues but just like in Java you can actually run a thread from a single line in Python.

We will be using the Thread Class from Python

from threading import Thread

Define the Function which you want to call.

def func1():
   print("Hello World")

Start a thread from one single line

Thread(target=func1).start()

That is how you start one liner thread in python.
For information on how to pass arguments to target function

How to use thread on just one line of python, not for all the script

3 Answers3