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download
Downloads the .deb file for the given package to the current directory. If a
package name contains a tilde character (“~”) or a question mark (“?”), it will be
treated as a search pattern and all the matching packages will be downloaded (see
the section “Search Patterns” in the aptitude reference manual).
By default, the version which would be installed with “aptitude install” is
downloaded. You can select a particular version of a package by appending
=<version> to the package name; you can select the version from a particular
archive or release by appending /<archive> or /<release> to the package name (for
instance: /unstable or /sid).
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Демек:
aptitude download "package-name"