&& et || dans un Script

[stardust]

Bonjour à tous, <BR> <BR>J'essaie de comprendre ce qui se passe losque la function start de ce script est appelée : <BR> <BR> <BR>########################################################################### <BR># <BR># Bourne shell functions for use with daemontools-0.70 <BR># <BR>########################################################################### <BR> <BR>#---------------------------------------------------------------------- <BR># copyright (C) 2001 e-smith, inc. <BR># <BR># This program is free software; you can redistribute it and/or modify <BR># it under the terms of the GNU General Public License as published by <BR># the Free Software Foundation; either version 2 of the License, or <BR># (at your option) any later version. <BR># <BR># This program is distributed in the hope that it will be useful, <BR># but WITHOUT ANY WARRANTY; without even the implied warranty of <BR># MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the <BR># GNU General Public License for more details. <BR># <BR># You should have received a copy of the GNU General Public License <BR># along with this program; if not, write to the Free Software <BR># Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 <BR>USA <BR># <BR># Technical support for this program is available from e-smith, inc. <BR># Please visit our web site <!-- BBCode auto-link start --><a href="http://www.e-smith.com" target="_blank">www.e-smith.com</a><!-- BBCode auto-link end --> for details. <BR>#---------------------------------------------------------------------- <BR> <BR># Source in the RedHat initscripts functions <BR> <BR>. /etc/rc.d/init.d/functions <BR> <BR># Now add some of our own and override some of RedHat's functions. <BR> <BR>pid() <BR>{ <BR> running $1 && (status $1 | /bin/awk '{print $4}' | /bin/sed -e <BR>'s/)//') <BR>} <BR> <BR>restart() <BR>{ <BR> stop $1 <BR> start $1 <BR>} <BR> <BR>running() <BR>{ <BR> if [ -n "$(status $1 | /bin/grep ': up (pid')" ] <BR> then <BR> return 0 <BR> else <BR> return 1 <BR> fi <BR>} <BR> <BR>sigalrm() <BR>{ <BR> running $1 && /usr/local/bin/svc -a $1 <BR>} <BR> <BR>sigcont() <BR>{ <BR> running $1 && /usr/local/bin/svc -c $1 <BR>} <BR> <BR>sighup() <BR>{ <BR> running $1 && /usr/local/bin/svc -h $1 <BR>} <BR> <BR>sigint() <BR>{ <BR> running $1 && /usr/local/bin/svc -i $1 <BR>} <BR> <BR>sigkill() <BR>{ <BR> running $1 && /usr/local/bin/svc -k $1 <BR>} <BR> <BR>sigstop() <BR>{ <BR> running $1 && /usr/local/bin/svc -p $1 <BR>} <BR> <BR>sigterm() <BR>{ <BR> running $1 && /usr/local/bin/svc -t $1 <BR>} <BR> <BR>start() <BR>{ <BR> /bin/echo -n "Starting $SERVICE:" <BR> running $1 || (/usr/local/bin/svc -u $1; /bin/sleep 1) <BR> running $1 && success "Starting $SERVICE" || failure "Starting <BR>$SERVICE" <BR> /bin/echo <BR>} <BR> <BR>status() <BR>{ <BR> /usr/local/bin/svstat $1 <BR>} <BR> <BR>stop() <BR>{ <BR> /bin/echo -n "Stopping $SERVICE:" <BR> running $1 && (/usr/local/bin/svc -d $1; /bin/sleep 1) <BR> running $1 && failure "Stopping $SERVICE" || success "Stopping <BR>$SERVICE" <BR> /bin/echo <BR>} <BR> <BR> <BR> <BR>Quelqu'un serait il me dire quelles est la différence entre : <BR> <BR>running $1 || <BR> <BR>et <BR> <BR>running $1 && <BR> <BR> <BR>Je pense que <BR>|| est un "ou" entre 2 actions <BR>et que <BR>&& est un "et" entre 2 actions <BR> <BR>Si j'ai bon, que font ces lignes : <BR> <BR>start() : <BR>running $1 || (/usr/local/bin/svc -u $1; /bin/sleep 1) <BR> <BR>running() <BR>if [ -n "$(status $1 | /bin/grep ': up (pid')" ] <BR> <BR>D'avance merci

[tomtom]

Un de mes profs disait... <BR>"quand on a compris les pipes, on a compris tout UNIX" <BR> <BR>Il avait pas tort <IMG SRC="images/smiles/icon_smile.gif"> <BR> <BR> <BR>donc && et || ce sont des pipes avec test..... <BR> <BR>en clair, <BR>fonction1 && fonction2 ca execute fonction1, puis ca execute fonction 2 uniquement si fonction1 a retourné un code reussite (zero). <BR> <BR>fonction1 || fonction2, ca execute fonction1 puis fonction2 si fonction1 a echoué... <BR> <BR>empilage.... <BR> <BR>fonction1 && fonction2 || fonction3 ca fait fonction1, si ok fonction2, si pas ok fonction3. <BR> <BR> <BR>Une application courante : <BR> <BR>ifdown eth1 && ifup eth1 (en gros, on arrete et si ca ùarche on redemarre....). <BR>ou du debugage : <BR> <BR>ping -c 1 site_distant && echo "connect ok" || restart_connect.. <BR> <BR>etc.... <BR> <BR>T.

[stardust]

Merci pour la clareté de tes explications.

[Muzo]

Merci, je viens d'apprendre un truc !! <IMG SRC="images/smiles/icon_biggrin.gif"> <BR> <IMG SRC="images/smiles/icon_bise.gif"> aux 2 pour la question et la réponse <BR> <BR>

[stardust]

clarté et non pas clareté <BR> <BR>désolé la france <IMG SRC="images/smiles/icon_biggrin.gif">