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Full Discussion: can't close stdin/stdout in shell
Top Forums Shell Programming and Scripting can't close stdin/stdout in shell Post 302396430 by Corona688 on Thursday 18th of February 2010 11:40:34 AM
Old 02-18-2010
can't close stdin/stdout in shell
Code:
#!/bin/sh
exec 0</dev/null
exec 1>/dev/null

ls -l /proc/self/fd >&2

produces
Code:
total 0
lr-x------ 1 tyler users 64 Feb 18 10:38 0 -> /proc/7886/fd
lrwx------ 1 tyler users 64 Feb 18 10:38 1 -> /dev/pts/4
lrwx------ 1 tyler users 64 Feb 18 10:38 2 -> /dev/pts/4

I've verified the shell is actually redirecting stdout as expected, but when I run ls it is not inheriting this change. If I leave out the >&2, it produces no output, meaning it's only re-redirecting stdout to my console when I don't redirect stdout into stderr -- in other words, it only redirects stdout back to the console when I tell it not to use stdout at all! Why is it restoring stdout at all?
Last edited by Corona688; 02-18-2010 at 12:58 PM.. Reason: fix typos in source
 

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LEARN ABOUT DEBIAN

ompi-iof

OMPI-IOF(1)							     Open MPI							       OMPI-IOF(1)

NAME

       ompi-iof, orte-iof - Displays a copy of the output streams from a process.

       NOTE: ompi-iof, and orte-iof are exact synonyms for each other. Using any of the names will result in exactly identical behavior.

SYNOPSIS

       ompi-iof [ options ]

Options
       ompi-iof will display a copy of the indicated stdout, stderr, and/or stddiag streams from the designated process.

       -pid | --pid
		 The pid of the mpirun executing the process whose streams are to be copied

       -stdout | --stdout
		 Display a copy of the specified process' stdout. If no options are specified, this will act as the default

       -stderr | --stderr
		 Display a copy of the specified process' stderr.

       -stddiag | --stddiag
		 Display a copy of the specified process' stddiag.

       -rank | --rank
		 The rank of the process whose output is to be copied.

DESCRIPTION

       ompi-iof  displays  a copy of the indicated stdout, stderr, and/or stddiag streams from the designated process. At this time, a ctrl-C must
       be used to terminate the program.  The program will terminate cleanly, telling the associated mpirun to close the requested streams  before
       exiting.

SEE ALSO

       orterun(1)

1.4.5								   Feb 10, 2012 						       OMPI-IOF(1)
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