Date: Wed, 25 Jul 2001 14:12:06 +0300 From: Maxim Sobolev <sobomax@FreeBSD.org> To: current@FreeBSD.org Cc: Julian Elischer <julian@elischer.org>, stable@FreeBSD.org Subject: Strange select(2) misbehaviour when linked with -pthread Message-ID: <3B5EA985.458B39B7@FreeBSD.org>
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Hi,
I found that the attached small program behaves very strangely when
linked with -pthread - it chews 100% CPU cycles while waiting in
select(2). This misbehaviour observed both on 5-CURRENT and 4-STABLE
systems. *weird*
-Maxim
P.S. And yes, I know that I ought to use NULL instead of &tv when I
want to wait indefinitely in select(2), but it is how some programs
work.
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filename="selectbug.c"
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/time.h>
#include <unistd.h>
int main()
{
int retval, fd;
u_int32_t timeout;
struct timeval tv;
fd_set mask;
fd = 0;
timeout = ~0;
tv.tv_sec = timeout/1000;
tv.tv_usec = (timeout%1000)*1000;
FD_ZERO(&mask);
FD_SET(fd, &mask);
retval = select(1, &mask, NULL, NULL, &tv);
exit(0);
}
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