From: Eli Barzilay <eli@barzilay.org>
To: linux-kernel@vger.kernel.org
Subject: Problem with select?
Date: Wed, 18 Jun 2003 04:49:58 -0400 [thread overview]
Message-ID: <16112.10166.989608.288954@mojave.cs.cornell.edu> (raw)
Hello,
When I run the following program, and block the terminal's output
(C-s), the `select' doesn't seem to have any effect, resulting in a
100% cpu usage (this is on a RH8, with 2.4.18). I wouldn't be
surprised if I'm doing something stupid, but it does seem to work fine
on Solaris.
Is there anything wrong with this, or is this some bug?
======================================================================
#include <unistd.h>
#include <fcntl.h>
int main() {
int flags, fd, len; fd_set writefds;
fd = 1;
flags = fcntl(fd, F_GETFL, 0);
fcntl(fd, F_SETFL, flags | O_NONBLOCK);
while (1) {
FD_ZERO(&writefds);
FD_SET(fd, &writefds);
len = select(fd + 1, NULL, &writefds, NULL, NULL);
if (!FD_ISSET(fd,&writefds)) exit(0);
len = write(fd, "hi\n", 3);
}
fcntl(fd, F_SETFL, flags);
}
======================================================================
--
((lambda (x) (x x)) (lambda (x) (x x))) Eli Barzilay:
http://www.barzilay.org/ Maze is Life!
next reply other threads:[~2003-06-18 8:36 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-06-18 8:49 Eli Barzilay [this message]
2003-07-24 5:28 ` Repost: Bug with select? Eli Barzilay
2003-07-25 13:41 ` Marco Roeland
2003-07-26 0:20 ` Ben Greear
2003-07-26 9:05 ` Marco Roeland
2003-07-26 0:35 ` Philippe Troin
2003-07-26 14:29 ` Eli Barzilay
2003-07-26 14:25 ` Eli Barzilay
2003-07-26 15:37 ` Marco Roeland
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