[CentOS] A newbie question about searching an installed packet

Hi,

I’m french and literally one. So I’m not really easy with Sheakespeare language. So, accept my apologies.

As write in subject, I’m a newbie about CentOS an all RedHat declines. I wrote a Shell script for ours Debians (all sort of Debian like) which verify which packets are present before running. I thought I had found an equivalent with « yum list installed | grep <packet> » command but I have sometime alerts about a lock because an other instance of « yum » is running.

I don’t understand why a simple « yum list » impose that! I suppose, like with « aptitude search », it is an understanding scorie.

I’m sure there is an other way to do what I want to do: just verify if a packet is, or not, installed.

Help?

Thanks

--
Pierre Malard

  « On ne peut pas pousser à fond l'éducation politique et l'éducation
    tout court de masses sans l'accompagner d'un développement
    économique, culturel et social parallèle. »
                                                   Romain Gary - "Les racines du ciel"
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- --> Ce message n’engage que son auteur <--

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