从线程的上下文中调用线程对象的方法

Question

I'm trying to make a call to one of a thread object's methods from the context of the thread using the object's handle. However, this isn't working and instead the call to the method is being made from the context of the main thread. Is there any way around this?

Here's some example code:

import threading

class ThreadTest(threading.Thread):
  def __init__(self):
    threading.Thread.__init__(self)
    print '\nInitializing ThreadTest\n'

  def call_me(self):
    ident = threading.current_thread().ident
    print '\nI was called from thread ' + str(ident) + '\n'

  def run(self):
    ident = threading.current_thread().ident
    print '\nStarting thread ' + str(ident) + ' for ThreadTest\n'
    self.call_me()

ident = threading.current_thread().ident
print '\nMain thread ID is ' + str(ident) + '\n'

tt = ThreadTest()
tt.start()
tt.call_me()

# Example Output:
#   Main thread ID is 140735128459616
#
#   Initializing ThreadTest
#
#   Starting thread 4400537600 for ThreadTest
#
#   I was called from thread 4400537600
#
#   I was called from thread 140735128459616

What I'm looking for is a way to make tt.call_me() be from the context of the thread such that current_thread().ident returns the same ID as it does when its called from the thread's run method.

Any ideas?

Answer 1

Python class methods can be called from any thread. That goes for the threading.Thread class too. When you wrote:

tt.call_me()

You were saying, "whatever thread happens to be running this code, please call tt.call_me". Since you were in main thread, the main thread made the call. Python doesn't automatically proxy the call to the thread.

The self.call_me line in the run method worked just fine. The 'run' method is the thread and anything it calls is in that thread.