Pass keyword arguments to target function in Python threading.Thread
PythonMultithreadingPython 2.7Python MultithreadingKeyword ArgumentPython Problem Overview
I want to pass named arguments to the target function, while creating a Thread object.
Following is the code that I have written:
import threading
def f(x=None, y=None):
print x,y
t = threading.Thread(target=f, args=(x=1,y=2,))
t.start()
I get a syntax error for "x=1", in Line 6. I want to know how I can pass keyword arguments to the target function.
Python Solutions
Solution 1 - Python
t = threading.Thread(target=f, kwargs={'x': 1,'y': 2})
this will pass a dictionary with the keyword arguments' names as keys and argument values as values in the dictionary. the other answer above won't work, because the "x" and "y" are undefined in that scope.
another example, this time with multiprocessing, passing both positional and keyword arguments:
the function used being:
def f(x, y, kw1=10, kw2='1'):
pass
and then when called using multiprocessing:
p = multiprocessing.Process(target=f, args=('a1', 2,), kwargs={'kw1': 1, 'kw2': '2'})
Solution 2 - Python
You can also just pass a dictionary straight up to kwargs:
import threading
def f(x=None, y=None):
print x,y
my_dict = {'x':1, 'y':2}
t = threading.Thread(target=f, kwargs=my_dict)
t.start()
Solution 3 - Python
Try to replace args
with kwargs={x: 1, y: 2}
.