Re: #518696 ITP: parallel -- build and execute command lines from standard input in parallel]
Phil's in hospital. Will reply towards end of week.
On Tuesday 10 March 2009, Chuan-kai Lin wrote:
> On Mon, Mar 09, 2009 at 10:57:57PM +0100, Samuel Thibault wrote:
> > I thought at first "it's not particularly convenient", then "well, so
> > what". Now I'm thinking "Mmm, but people won't know they should do
> > it and blame xargs for being broken". Also annotate-output is not
> > enough when programs e.g. output Packages entries, which not only
> > should be line-atomic, but also paragraph-atomic...
> Below is what I had in mind when I mentioned adapting annotate-output
> to a different "atomic-output" script. This script is usefull not just
> with "xargs -P", but also with "make -j" and with standard background
> jobs (shell & operator), all of which produce mixed output.
> Similarly, about matching the number of parallel jobs with the number
> of processors/cores, we can write a script "ncpus" which returns the
> number of processors/cores/hyper-threads. You can use the ncpus script
> with xargs, with make, or with my new project mdm (mdm.berlios.de)...
> I consider separating these concerns (output management, processor
> thread detection) into small, separate, and reusable scripts a cleaner
> solution. Of course, doing it this way requires some user education,
> so a few manpage updates (for example, adding atomic-output and ncpus
> to the SEE ALSO section of xargs) may be in order.
> #! /bin/bash
> # Display stdout and stderr output after program termination
> # Adapted from annotate-output by Chuan-kai Lin
> # Original annotate-output author info and copyright notice as follows
> # this script was downloaded from:
> # http://jeroen.a-eskwadraat.nl/sw/annotate
> # and is part of devscripts 2.10.46
> # Executes a program annotating the output linewise with time and
> stream # Version 1.2
> # Copyright 2003, 2004 Jeroen van Wolffelaar <email@example.com>
> # This program is free software; you can redistribute it and/or modify
> # it under the terms of the GNU General Public License as published by
> # the Free Software Foundation; version 2 of the License
> # This program is distributed in the hope that it will be useful,
> # but WITHOUT ANY WARRANTY; without even the implied warranty of
> # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> # GNU General Public License for more details.
> # You should have received a copy of the GNU General Public License
> # along with this program; if not, write to the Free Software
> # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
> OUT=`mktemp /tmp/atomic.XXXXXX` || exit 1
> ERR=`mktemp /tmp/atomic.XXXXXX` || exit 1
> echo "------ `date +%H:%M:%S` Started $@" > $ERR
> echo "------ STDERR" >> $ERR
> echo "------ STDOUT" >> $OUT
> "$@" >> $OUT 2>> $ERR ; EXIT=$?
> cat $ERR
> cat $OUT
> echo "------ `date +%H:%M:%S` Finished with exitcode $EXIT"
> rm -f $OUT $ERR
> exit $EXIT
> Chuan-kai Lin
Philip Charles; 39a Paterson Street, Abbotsford, Dunedin, New Zealand
+64 3 488 2818 Fax +64 3 488 2875 Mobile 027 663 4453
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