$ curl cheat.sh/
 cheat.sheets:apt-cache 
# apt-cache
# Query the APT cache

# Search for package PKG. Both package names and their descriptions are
# searched for a REGEX match; to avoid this behavior, you may use the `-n`
# flag, which will only look for a match in the package name.
apt-cache search 'PKG'

# Regarding the above, although multiple package names may not be specified, -
# it's possible to use ERE to easily and quickly get around this limitation.
# Here, all 3 packages (PKG1, PKG2, and PKG3) will be sought.
apt-cache search '(PKG1|PKG2|PKG3)'

 cheat:apt-cache 
---
tags: [ packaging ]
---
# To find packages matching <phrase>:
apt-cache search <phrase>

# To display package records for the named package(s):
apt-cache show <package>...

# To display reverse dependencies of a package:
apt-cache rdepends <package>

# To display package versions, reverse dependencies and forward dependencies of
# a package:
apt-cache showpkg <package>

# To display package installation status and what version is available from
# its repository:
apt-cache policy <package>

 tldr:apt-cache 
# apt-cache
# Debian and Ubuntu package query tool.
# More information: <https://manpages.debian.org/latest/apt/apt-cache.8.html>.

# Search for a package in your current sources:
apt-cache search query

# Show information about a package:
apt-cache show package

# Show whether a package is installed and up to date:
apt-cache policy package

# Show dependencies for a package:
apt-cache depends package

# Show packages that depend on a particular package:
apt-cache rdepends package

$
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