Thanks, I was sure there were a relevant solution. That’s exactly what I was looking for :-) > Le 8 nov. 2018 à 21:02, Kenneth Porter <shiva at sewingwitch.com> a écrit : > > On 11/8/2018 11:52 AM, Pierre Malard wrote: >> 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. > > Yum is a layer on top of the RPM package database. Yum manages dependencies and figures out which additional packages to install (or remove) when you want to install a new package. Yum regularly runs a cron job to check for updates to existing packages and that cron job locks the yum database. That's probably why your interactive job complains that it can't lock the database. > > To just query what's installed, you can use the lower-level RPM commands. They don't require a lock on the yum database. The RPM database is only locked when you actually install or remove a package. > > I use this to see if a package is installed: > > rpm -qa | grep -i package-name > > I use the same command when I can't remember the exact name and capitalization of a package. That's why I include the -i in the grep command. > > > _______________________________________________ > CentOS mailing list > CentOS at centos.org > https://lists.centos.org/mailman/listinfo/centos -- Pierre Malard « C'est bien plus beau lorsque c'est inutile » E Rostand - "Cyrano de Bergerac" |\ _,,,---,,_ /,`.-'`' -. ;-;;,_ |,4- ) )-,_. ,\ ( `'-' '---''(_/--' `-'\_) πr perl -e '$_=q#: 3|\ 5_,3-3,2_: 3/,`.'"'"'`'"'"' 5-. ;-;;,_: |,A- ) )-,_. ,\ ( `'"'"'-'"'"': '"'"'-3'"'"'2(_/--'"'"' `-'"'"'\_): 24πr::#;y#:#\n#;s#(\D)(\d+)#$1x$2#ge;print' - --> Ce message n’engage que son auteur <-- -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 901 bytes Desc: Message signed with OpenPGP URL: <http://lists.centos.org/pipermail/centos/attachments/20181108/2496dc79/attachment-0005.sig>