Select hangs after some reads

alsmeirelles at gmail.com alsmeirelles at gmail.com
Thu Jun 8 05:27:14 CEST 2006


Hi,

I'm building a multithreaded application and I encountered a tiny and
annoying problem. I use a select to wait for data to be read from a
socket, after some reads, the select simply blocks and stays that way
until I close the connection on the other side of the socket. When the
socket is closed on the writer end the select releases and then I get
only empty strings from the socket.
My question is this: Why did it block? The reading has never ended,
every test I make I write 50 requests (wich are strings) to the socket
and I have read the maximum of 34 requests. I'm using winPdb to take a
closer look on what's happening and I see the threads blocked on this
same select. If I send anything more through the socket, the select
releases for a thread, despite the other data that is still unread.

This is the select:
 rd,w,e = select.select([self.rfd],[],[])

self.rfd is the fileno of the file object returned by the makefile
method from the socket object.

I know that's some buffer behavior that I'm missing but I don't know
what it is.

anything is helpfull, If I'm beeing stupid you can say it.
thanks




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