python - blocking sockets and select -

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i'm playing around sockets, , i'm having doubts using blocking sockets select.let's assume i'm tracking potential readers. right in thinking select go through first socket in list , if data available return , if not block until select's timeout expires? when other sockets in read list checked select?

let me illustrate python example simplicity:

servsock = socket.socket(socket.af_inet, socket.sock_stream) servsock.bind(("", 2500)) servsock.listen(15) servsock.setblocking(1)  readlist = [servsock]  while 1:     (sread, swrite, sexc) =  select.select(readlist, [], [] );       sock in sread:          #received connect server socket         if  sock == servsock:          (newsock, address) = servsock.accept()             newsock.setblocking(1)             print "i got connection ", address             readlist.append(newsock)             newsock.send("you're connected select server")         else:             recv_msg = sock.recv(5)              if recv_msg == "":                 (host, port) = sock.getpeername()                 print "client %s:%s closed connection" % (host,port)                 sock.close()                 readlist.remove(sock)             else:                 (host, port) = sock.getpeername()                 print "client %s:%s sent: %s "% (host,port,recv_msg)

since they're blocking sockets, select block when testing see if socket in list has data read?

the select() c api returns list of sockets readable. assuming python's wrapper same, sread contain multiple elements if multiple sockets readable.

a blocking socket block if there no data present, after select() call indicated there data, can assume one call recv not block.


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