What is apt-cache used for?

Can anyone please define what exactly the APT cache is?

Solution 1:

apt-cache is a command to manipulate and obtain information from the packages at apt's cache.

It creates a repository of information about the packages that are avaiable from your sources list, so this way you can search packages and information about it.

Let's say you want to install a chat program but you don't know the name of a package for it.

You would open a console and type:

sudo apt-cache search chat

This would return a list of packages available and that refer to the word chat.

Typical operations with apt-cache:

apt-cache add

Adds a package file to the source cache.

apt-cache gencaches

Builds both the package and source cache

apt-cache showpkg

Show some general information for a single package

apt-cache stats

Show some basic statistics

apt-cache dump

Show the entire file in a terse form

apt-cache dumpavail

Print an available file to stdout

apt-cache unmet

Show unmet dependencies

apt-cache check

Check the cache a bit

apt-cache search

Search the package list for a regex pattern

apt-cache show

Show a readable record for the package

apt-cache depends

Show raw dependency information for a package

apt-cache pkgnames

List the names of all packages

apt-cache dotty

Generate package graphs for GraphVis

Don't forget to add package name after the commands listed above.

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