Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!udel!haven!adm!news
From: mnl%IDTSUN1.E-TECHNIK.TH-DARMSTADT.DE@BRL.MIL (Michael@CUNYVM.CUNY.EDU N. Lipp)
Newsgroups: comp.unix.questions
Subject: reading on sockets when connection breaks
Message-ID: <25205@adm.brl.mil>
Date: 6 Dec 90 04:18:10 GMT
Sender: news@adm.brl.mil
Lines: 25

Hello,

I have a program that establishes a TCP-connection with another machine,
requests the server to send some packets of data and then does a

while (read (fd, &packet, sizeof (packet)) == sizeof (packet)) { ... }

This program hangs frequently. I made it QUIT and found it hanging in the
read. As this program frequently connects to diskless machines that are
switched off at night, I assume that the connection comes down while
the program is reading.

I am wondering: shouldn't read return with an error status if the connection
breaks? As it apparently does not, what is the most reasonable fix?
A blocking read with timeout comes to my mind, but what is the best
way to do this?

Thanks Michael

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