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Top Forums UNIX for Beginners Questions & Answers Output of until to file versus stdout Post 303032331 by stomp on Friday 15th of March 2019 09:51:21 AM
Old 03-15-2019
Quote:
Originally Posted by Xubuntu56
Why does this until false; do history | head -5; done
result in a stdout infinite loop, yet until false; do history | head -5 > hist5; done
only writes it once to file hist5? Furthermore, I can hear the hard drive working on the 2nd command until I end the process, but the history | head -5 is only written once.

It does not write once. It writes continously without break the same 5 lines into hist5 file over and over and generates considerable load at your machine. Since every session has its own history this makes no sense to do.


I'm unsure, but I assume .bash_history file is written at logout. If you want to see another sessions history with this, this will not work.
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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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