On Wed, Oct 24, 2012 at 5:31 AM, Uros Bizjak <ubiz...@gmail.com> wrote: > On Wed, Oct 24, 2012 at 2:18 PM, Andreas Schwab <sch...@linux-m68k.org> wrote: >> Uros Bizjak <ubiz...@gmail.com> writes: >> >>> To answer my own question: >>> >>> dup(4) = 9 >>> ... >>> close(9) = 0 >>> dup(4) = -1 EBADF (Bad file descriptor) >>> >>> Test is calling dup on a closed file descriptor. >> >> FD 4 is most likely closed by one of the cloned threads. Use strace -f >> to follow them. > > Yes, indeed! Attached strace -f record confirms this on alpha. > > The same happens on x86_64, but for some reason x86_64 doesn't > complain when executing dup(2) on closed FD.
The test execs itself by calling the fork and execve functions in libc. It is the child process that closes the FD after it forks. >From the point of view of the parent process, the FD should still be open. I don't think you attached the strace -f output so I can't confirm this. Ian
