How to deal with PATH in installation script for my applications?

Question

I want to create postinst script for my application debian package and I need to modify /etc/environment file (add some path to it) to make my application bin directory content accessible globally in system.

With my current knowledge all I can do now is:

• remove last " character in /etc/environment file (for now I don't know how to do it in bash, maybe I will try this: How can I remove the last character of a file in unix? )
• append :
• append /usr/some/directory/bin (my application bin dir) to that file
• append "

Is there easier way to add some path to environment variables permanently and globally?

Background:

I'm working on few packages to automate installation/deployment process, I have few things like Java, bash scripts, drivers and some c/c++ tool applications to deploy on many devices.

Answer 1

The path isn’t necessarily defined in /etc/environment, and even if it is, there is no guarantee that path will end up being the path that’s used by end users.

In a Debian package, to make commands available generally, you should install them to a directory which is expected to be on the path, typically /usr/bin. If you can’t move your binaries there, it’s fine to add wrapper scripts in /usr/bin which know where to find the “real” commands.

For Java, you shouldn’t try to re-package things yourself; use java-package to package Oracle JDKs and JREs, or the OpenJDK packages already available in Debian. See Installing JDK in a FHS-compliant way and Ways to configure alternative installations of Oracle JDK on Ubuntu? for details.