apt-cache --version (return code: 0)
apt 1.2.19 (amd64)
apt-cache --help (return code: 0)
apt 1.2.19 (amd64) Usage: apt-cache [options] command apt-cache [options] show pkg1 [pkg2 ...] apt-cache queries and displays available information about installed and installable packages. It works exclusively on the data acquired into the local cache via the 'update' command of e.g. apt-get. The displayed information may therefore be outdated if the last update was too long ago, but in exchange apt-cache works independently of the availability of the configured sources (e.g. offline). Most used commands: showsrc - Show source records search - Search the package list for a regex pattern depends - Show raw dependency information for a package rdepends - Show reverse dependency information for a package show - Show a readable record for the package pkgnames - List the names of all packages in the system policy - Show policy settings See apt-cache(8) for more information about the available commands. Configuration options and syntax is detailed in apt.conf(5). Information about how to configure sources can be found in sources.list(5). Package and version choices can be expressed via apt_preferences(5). Security details are available in apt-secure(8).