rpm:tldr:e45e3

The command "rpm --query --file ${-etc-postfix-main-cf}" is used to query the rpm database for the package that owns a specific file, in this case, "-etc-postfix-main-cf". Let's break down the command:

• "rpm": It is a command-line tool in Linux used to manage RPM packages.
• "--query": This option is used to query information about installed packages.
• "--file": This option is used to specify the file to search in the rpm database and find out which package it belongs to.
• "${-etc-postfix-main-cf}": It represents the file name or path you want to search. In this case, it seems like it is meant to be a placeholder, as "${-etc-postfix-main-cf}" doesn't provide a valid filename or path.

To use this command correctly, you need to replace "${-etc-postfix-main-cf}" with the actual file name or path you want to search. It should look something like this:

rpm --query --file /etc/postfix/main.cf

This modified command will search the rpm database for the package that owns the file "main.cf" located in the "/etc/postfix/" directory.