This is a part two (link to part one) for my home assignment for Tero Karvinen’s course on linux servers. On this part I will build and install a package that will add an executable shell script and an alias for it for all users.

Now to create a new package with a shell script file.

mkdir mmm-command
cd mmm-command
equivs-control mmm-command

The ‘equivs-control’ command creates a file called ‘mmm-command’, which contains the basic structure for a ‘.deb’ package.

The content I replaced in  ‘mmm-command’ (I removed the other ones, which are not so relevant):

Section: misc
Priority: optional
Homepage: https://miro.metsanheimo.fi
Standards-Version: 3.9.2

Package: mmm-command
Version: 0.0.1
Maintainer: Miro Metsänheimo <miro@metsanheimo.fi>
Files: mmm-command.sh /bin # Copy the command file to the bin folder for use of all users
Postinst: mmm-command-install.sh # Run the install script to make the alias after installation
Architecture: all
Description: My new command
 My new command

Here we have two lines that do something crucial:

• Files: list of files to be installed and compiled in to the ‘.deb’ package.
• Postinst: a script to run after the installation

Then we create the ‘mmm-command.sh’ file mentioned above with the content:

nano mmm-command.sh

#!/bin/bash
echo "An example scipt that installs with my .deb package to all users."

This file is just a simple echo line just to make sure the script works.

And then the ‘mmm-command-install.sh’ file with the content:

nano mmm-command-install.sh

#!/bin/bash

# If the file doesn't exist, create it
if [ ! -f /etc/profile.d/00-aliases.sh ]
then
 touch /etc/profile.d/00-aliases.sh
fi
# Append the alias to the created file
echo "alias mmm-command='/bin/mmm-command.sh'" >> /etc/profile.d/00-aliases.sh
source /etc/profile # Reload the commands

Here we create a new file in the ‘profile.d’, because this will last longer and works after updates. The ’00-‘ is to make sure the script is ran first.

And then we build the package creating a file called ‘mmm-command_0.0.1_all.deb’ and install the package with ‘gdebi’:

equivs-build mmm-command
sudo gdebi mmm-command_0.0.1_all.deb

And then a tryout:

xubuntu@xubuntu:/$ mmm-command
An example scipt that installs with my .deb package to all users.

Works!

Sources

Class by Tero Karvinen

SH command in a package

Alias for all users

Shell IF