Sometimes we refer to a file or a command and you might wonder, in which package it will be found. Fortunately the Debian repositories not only contain information about all the binary packages provided, but also all the files shipped with them. This information is stored in files named Contents-arch.gz and Contents-udeb-arch.gz. This information is not automatically downloaded by APT. Instead it needs the apt-file update command (from the similar named package) to retrieve the contents of all package sources mentioned in /etc/apt/sources.list. By default it downloads Contents*.pdiff files as described in sidebar DICA Atualização incremental to reduce the amount of data necessary to be downloaded. To update the database on a weekly base, the following entry can be added to /etc/crontab if convenient.

@weekly root test -x /usr/bin/apt-file && /usr/bin/apt-file update >> /dev/null 2>&1

Depois do banco de dados ser atualizado, o comando apt-file search padrão vai listar todos os pacotes que contém um arquivo ou caminho contendo o padrão.

$ apt-file search bin/axi-cache
apt-xapian-index: /usr/bin/axi-cache

O comando apt-file list pacote vai listar, ao invés disto, todos os arquivos enviados com o pacote.