I forgot to mention that with this code:
total = ''
while True:
data = s.recv(1024)
total += data
if (total != ''):
print total
total = ''
Everything is fine.
I am still looping but I get the complete data flow sent by the remote server.
The data flow is not corrupted with extra characters.
But I do not detect the closing of the socket on the remote server.
Why is recv not blocking !!!
Le samedi 23 août 2014 10:23:14 UTC+2, Arthur Clarck a écrit :
> Hello,
>
>
>
> I am starting socket scripting with python.
>
> I do understand from the doc that a socket is bmocking by default.
>
> I wrote 2 basics script to verify this behaviour.
>
>
>
> my "tcp_server.py":
>
>
>
>
>
> import socket, sys
>
> s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
>
>
>
> HOST = '192.168.0.103'
>
> PORT = 1060
>
>
>
> s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
>
> s.bind((HOST, PORT))
>
> while True:
>
> s.listen(1)
>
> print 'Listening at', s.getsockname()
>
> sc, sockname = s.accept()
>
> print 'We have accepted a connection from', sockname
>
> print 'Socket connects', sc.getsockname(), 'and', sc.getpeername()
>
> while True:
>
> data = sc.recv(1024)
>
> if data:
>
> print 'Got from client:', repr(data)
>
> data = ''
>
> else:
>
> #raise EOFError('socket closed')
>
> print 'socket closed by remote client'
>
> sc.close()
>
> sys.exit()
>
>
>
>
>
> and my "tcp_client.py"
>
>
>
> import socket, sys, time
>
> s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
>
>
>
> HOST = '192.168.0.103'
>
> PORT = 1060
>
>
>
> s.connect((HOST, PORT))
>
> print 'Client has been assigned socket name', s.getsockname()
>
> while True:
>
> data = raw_input('cmd:')
>
> if (data == '\x05'):
>
> print 'closing socket and exit'
>
> s.close()
>
> sys.exit()
>
> s.sendall(data)
>
>
>
> When both are running everything what I type in the client is received by the
> server.
>
> When nothing is sent from the client the server is waiting (socket is
> blocking)
>
> for next datas.
>
> If I close the client with Ctrl-E (or a kill) the socket on the server is
> getting a null value and the server exit.
>
> So everything is fine. And everything is clear in my mind.
>
>
>
> The problem I have now is the following.
>
> I have a script to connect to some telecom service.
>
> The script is forking (parent/child)
>
> The child is only reading what comes from the remote server.
>
> Here the problematic code:
>
>
>
> total = ''
>
> while True:
>
> data = s.recv(1024)
>
> total += data
>
> if (data == ''):
>
> print 'remote site is closed'
>
> s.close()
>
> sys.exit()
>
>
>
> What is happening is that I got some datas from the remote site,
>
> Something like 'Contacting BH: ...'
>
> But directly followed by 'remote site is closed.
>
> And if I remove the 2 lines (s.close;sys.exit) my script is looping
>
> So it means data==''
>
> This makes no sense at all.
>
> Why is the socket not waiting for the next datas flow ??
>
> Why is the socket not blocking ?
>
>
>
>
>
> With Perl I just have to write:
>
>
>
> while (sysread($socket,$data,1024)){
>
> syswrite(STDOUT,$data)
>
> }
>
>
>
> And it works perfectly.
>
>
>
> Any hint about what I missed in Python ?
>
>
>
> kr,
>
> Arthur.
--
https://mail.python.org/mailman/listinfo/python-list
