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@ishworgurung
Created May 24, 2012 07:15
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So, how can I use kqueue/kevent on BSD/Mac using Python?
#!/usr/bin/env python
"""
Example on using Kqueue/Kevent on BSD/Mac
using Python.
The TCP server essentially echoes back the
message it receives on the client socket.
"""
__author__ = "Ishwor Gurung <ishwor@develworx.com>"
__license__ = "3 clause BSD"
from socket import socket, \
AF_INET, SOCK_STREAM,\
SOL_SOCKET, SO_REUSEADDR,\
SHUT_WR
import sys
import select
BUFSIZE = 512
def handle_connection(cl_socket):
"""
Handle each client socket. Receive data on it and send
the data back to the client. If there are no more data
available on the read side, shutdown and close the
socket.
"""
while True:
m = cl_socket.recv(BUFSIZE)
if m and len(m)>0:
cl_socket.send(m)
else:
cl_socket.shutdown(SHUT_WR)
cl_socket.close()
break
def main():
s = socket(AF_INET, SOCK_STREAM)
s.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)
s.bind(("127.0.0.1",10000))
s.listen(10)
kq = select.kqueue()
# Initialise the master fd(s.fileno()) from server socket
kevent = select.kevent(s.fileno(),
filter=select.KQ_FILTER_READ, # we are interested in reads
flags=select.KQ_EV_ADD | select.KQ_EV_ENABLE)
while True:
revents = kq.control([kevent], 1, None)
for event in revents:
# If the kernel notifies us saying there is a read event available
# on the master fd(s.fileno()), we accept() the
# connection so that we can recv()/send() on the the accept()ed
# socket
if (event.filter == select.KQ_FILTER_READ):
cl,_ = s.accept()
handle_connection(cl)
if __name__=="__main__":
sys.exit(main())
@rensg001
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@xmo-odoo you are right.

@orklann
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orklann commented Apr 27, 2017

@ishworgurung
handle_connection is blocking due to the recv(), send() methods of the server socket is blocking, can we avoid using thread to fix this blocking, and just use non-blocking sockets for recv(), send() in this context?

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