Use shell script to count separate line entries inside a pipe to see how many entries got filtered out. It can be useful in some scenarios, especially for testing.
Verify package contents by hand or use simple shell script to automate this process.
Recently, I have parsed logs of several applications to generate custom weekly reports. It was very interesting exercise. I created two shell scripts to illustrate the whole idea by parsing HAProxy log files, so I could remember it in the future.
I have already described how to list the contents of specified package using apt-file utility, but you do not need it to check the contents of downloaded package.
Create simplest possible meta-package to install multiple software packages at once and quickly setup familiar environment.
Make iptables configuration persistent using systemd file with additional possibility to disable firewall after defined period of time.
Display reverse dependencies to inspect which packages depend on given application or library.
Make iptables configuration persistent using custom service file with additional features like configurable wait time, so you can safely interrupt execution and test mode that will disable firewall after defined period of time.
I have already described how to copy answers to the configuration questions for Debian packages, but there is an easier way to read and insert new values into the debconf database.
Perform simple incremental backup using rdiff-backup utility.