[MPICH] Redirecting standard/error io

[William Gropp]

At 03:27 AM 1/9/2006, David Minor wrote:
>Yes I'm having a specific problem, redirecting didn't help. I'm spawning
>mpiexec from an application with a simple command line interface. After
>mpiexec is spawned it seems like the spawned process is eating some of
>the stdin to my application. I need to execute commands numerous times
>before they're read on the stin of my app. My current workaround is to
>set up a pipe re=route st/in-out for mpiexec, but I miss most of the
>error messages this way.

Is there an easy way to reproduce the problem that you're seeing?  Which 
mpiexec are you using (mpd or gforker or something else)?  How are you 
spawning the mpiexec, and from what environment (e.g., spawning from within 
perl may leave FDs shared between processes if you aren't very careful).

Bill


>David
>
>-----Original Message-----
>From: William Gropp [mailto:gropp at mcs.anl.gov]
>Sent: Monday, January 09, 2006 1:39 AM
>To: David Minor
>Cc: mpich-discuss at mcs.anl.gov
>Subject: Re: [MPICH] Redirecting standard/error io
>
>At 02:40 AM 12/26/2005, David Minor wrote:
> >In mpiexiec, is there a way to direct standard input to /dev/null
>and/or
> >a way to direct standard and error output to a file?
>
>As Rusty mentions, this should work for mpd.  The gforker version of
>mpiexec has a bug in the current release that sends both stdout and
>stderr
>to stdout, but you should be able to redirect stdout to a file or to
>/dev/null .  For our nightly tests, we redirect stdout and stderr to a
>file.  Is there a particular problem that you are having?  We'd like
>this
>to work just like it was any other Unix command.
>
>Bill
>
>
> >David Minor
> >Orbotech
>
>William Gropp
>http://www.mcs.anl.gov/~gropp

William Gropp
http://www.mcs.anl.gov/~gropp