Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!psuvax1!brutus.cs.uiuc.edu!samsung!uunet!servio!penneyj
From: penneyj@servio.UUCP (D. Jason Penney)
Newsgroups: comp.unix.wizards
Subject: Re: sockets and select
Keywords: socket select
Message-ID: <380@servio.UUCP>
Date: 28 Feb 90 19:33:48 GMT
References: <4309@helios.TAMU.EDU> <132218@sun.Eng.Sun.COM> <4990@scolex.sco.COM>
Reply-To: penneyj@servio.UUCP (D. Jason Penney)
Distribution: usa
Organization: Servio Logic Development Corp.; Beaverton, OR
Lines: 25

In article <4990@scolex.sco.COM> natei@sco.com writes:
>"Ready" for reading/writing probably means that the read or the write
>will filled without blocking, and since the NDELAY bit has been set,
>read() will always work without blocking.
>
>You should either
>	(use NDELAY && not use select())
>		||
>	(use select() && not NDELAY)
>-- 

If I came across a system that did this, I would regard it as horribly
broken.  I use select() on non-blocking sockets in SunOS 4.0, Ultrix, 
Sony NEWS-OS, AIX, and other places, and on NONE of them does select() 
return a bit in readfd's unless there is at least one byte to read.

Since 0 bytes is used in both nonblocking and blocking mode to indicate
eof, if I saw that a socket was ready to read with 0 bytes left to read
in it, I would immediately close() it.

--J
-- 
D. Jason Penney           Ph: (503) 629-8383
Beaverton, OR 97006       uucp: ...uunet!servio!penneyj (penneyj@slc.com)
"Computers are useless; they can only give answers" -- Picasso