Hi Gilles, No, it is not a problem for my applications.
I would have assumed, that both are using a pipe to orted+tty or whatever infrastructure is used. Different behaviour is for me often a sign that something is going wrong. So better ask. ;) Regards CHrsitoph ----- Original Message ----- From: "Gilles Gouaillardet" <[email protected]> To: "Open MPI Developers" <[email protected]> Sent: Monday, July 27, 2015 3:28:12 PM Subject: Re: [OMPI devel] stdout, stderr reporting different values for isatty Christoph, that is correct stdout is a tty and stderr is not. it is a pipe to orted. I do not think that would be hard to change. is this a source of problem for your applications ? note this kind of behavior can be caused by the batch manager. if you use slurm and srun instead of mpirun, I am not even sure stdout is a tty. Cheers, Gilles On Monday, July 27, 2015, Christoph Niethammer < [email protected] > wrote: Hello, I know, using stdout and stderr within MPI programs is in no way good. Nevertheless I found that - and now wonder why - isatty inside an MPI program reports different values for stdout and stderr in Open MPI: # Running as non MPI program: ./isatty-test [0/1] stdout FILENO: 1, TTY: 1 [0/1] stderr FILENO: 2, TTY: 1 # Running with Open MPI 1.8.7: mpirun -np 2 ./isatty-test [1/2] stdout FILENO: 1, TTY: 1 [1/2] stderr FILENO: 2, TTY: 0 [0/2] stdout FILENO: 1, TTY: 1 [0/2] stderr FILENO: 2, TTY: 0 ... not sure if this is good or bad. Both are forwarded correctly to the tty as far as I see... Redirecting stdout or stderr to files does not change anything in the Open MPI case. Best regards Christoph Niethammer PS: MPICH reports in all cases 0 for isatty() on stdout and stderr. _______________________________________________ devel mailing list [email protected] Subscription: http://www.open-mpi.org/mailman/listinfo.cgi/devel Link to this post: http://www.open-mpi.org/community/lists/devel/2015/07/17713.php _______________________________________________ devel mailing list [email protected] Subscription: http://www.open-mpi.org/mailman/listinfo.cgi/devel Link to this post: http://www.open-mpi.org/community/lists/devel/2015/07/17714.php
