Release components - debs, snaps, images, containers
The version of CMake installed by APT on Ubuntu 18.04 is currently 3.10.2.This version might not be new enough for some software, so this tutorial will show you how to remove the old version and update it to the latest using either Snappy or building from source. Ubuntu releases are made semiannually by Canonical Ltd, the developers of the Ubuntu operating system, using the year and month of the release as a version number.The first Ubuntu release, for example, was Ubuntu 4.10 and was released on 20 October 2004. Consequently, version numbers for future versions are provisional; if the release is delayed until a different month (or even year) to that.
A release of Ubuntu is made through several different channels. What you consume will depend on where you are and what your interests happen to be.
The heart of Ubuntu is a collection of 'deb' packages which are tested and integrated so that they work well as a set. Debs are optimised for highly structured dependency management, enabling you to combine debs very richly while ensuring that the necessary software dependencies for each deb (themselves delivered as debs) are installed on your machine.
Ubuntu also supports 'snap' packages which are more suited for third-party applications and tools which evolve at their own speed, independently of Ubuntu. If you want to install a high-profile app like Skype or a toolchain like the latest version of Golang, you probably want the snap because it will give you fresher versions and more control of the specific major versions you want to track.
Snaps each pick a 'base', for example, Ubuntu18 (corresponding to the set of minimal debs in Ubuntu 18.04 LTS). Nevertheless, the choice of base does not impact on your ability to use a snap on any of the supported Linux distributions or versions — it's a choice of the publisher and should be invisible to you as a user or developer.
A snap can be strictly confined, which means that it operates in a secure box with only predefined points of access to the rest of the system. For third-party applications, this means that you will have a very high level of confidence that the app can only see appropriate data that you have provided to it. Snaps can also be 'classic' which means that they behave more like debs, and can see everything on your system. You should make sure you have a high level of confidence in the publisher of any classic snap you install since a compromise or bad faith behaviour in that code is not confined to the app itself.
It is also common to consume Ubuntu as an image on a public cloud, or as a container. Ubuntu is published by Canonical on all major public clouds, and the latest image for each LTS version will always include security updates rolled up to at most two weeks ago. You may benefit from installing newer updates than that, but the base image you boot on the cloud should always be the current one from Canonical to ensure that it is broadly up to date and the number of updates needed for full security is minimal.
Canonical also publishes a set of images and containers that you can download for use with VMware or other local hypervisors and private cloud technologies. These include standard Ubuntu images on the Docker Hub and standard images for use with LXD and MAAS. These images are also kept up to date, with the publication of rolled up security updated images on a regular cadence, and you should automate your use of the latest images to ensure consistent security coverage for your users.
In this tutorial, we are going to show how to install the latest python on Ubuntu 18.04 machine using the terminal. Also, we will create a virtual environment and a simple program and run it. At the moment of writing this article, the latest stable version of python was 3.6.5 but the process of installing allows you to install the latest version by changing just the version number.
Note that Ubuntu 18.04 has python 3 preinstalled. However, we are going to show how to install it, update and uninstall.
How to install latest python
Before installing the latest version of python check the version of python currently installed on your machine. To do so you can run:
The Latest Ubuntu Lts
or
If there are several versions installed on your machine you can run the following command to view all versions:
If you want to install the latest version of python3 on your Ubuntu18 machine you can run:
or if it's already preinstalled, you can run the command below to update to latest version.
However, if you want to install it manually you can use the source code. To do so, follow the instruction below.
How to install python from source
To install the latest python from source, get the download link of the latest version from python's official website and download it to your Ubuntu machine. To do so you can run:
Once it is downloaded, extract the archive using the command below:
Change your directory to the newly created Python3.6.5 folder by running:
and run the configure script to check the build
Once the check has been completed run the following commands in the mentioned order to install python 3.6.5
However, if there wasn't need to use zlib1g-dev package before, you'll get an error of it's absence, which will look like this:
To install the missing package run:
Journey windows diary. After package installation run the sudo make and sudo make install commands once more. After installation is completed check the installed version with the following command:
Output must look like this:
How to update python to latest version
To update python to the latest version, you can run:
or if you have installed manually from source, you must uninstall the previous version and install the latest version or the one you want. The steps of how to do so are described in the section below.
How to uninstall python
To uninstall python from your Ubuntu 18 machine, run:
What Is The Latest Ubuntu Lts Version
Note that you cannot mention major python3 version as it is being used by the system, but you can uninstall minor version which is preinstalled on your machine.
If you have installed python from source and need to update it, you must uninstall the previous one and repeat the installation steps which are described above in this article. As this method if installation locates python files in /usr/local/bin path, you must remove python files from that path. To do so you can run the following commands:
Once all files are removed you can proceed to the installation of newer version.
How to setup virtual environment for python3
Virtual environment for python is an isolated space on your computer for Python projects, which allows each of your projects to have its own set of dependencies and don't disturb any other project. Inside the virtual environment, you can use python and pip commands instead of python3 and pip3 accordingly. Outside of an environment, you must use python3 and pip3 commands for running Python 3.
Following the steps below you can setup a virtual environment for python3 and use it to develop applications.
First of all you need to check if pip (python package manager) installed along with your python installation. If you installed python from source, pip is being installed along with python. To check pip version run:
Output must look like the one below:
If pip isn't installed on your machine, run the following command to install it:
Once pip is installed you can run the following command to install python packages:
Besides pip you need some more packages that need to be installed as prerequisites. To install them all, run:
Once all prerequisites are installed you can proceed to virtual environment creation. To do so follow the steps below:
Install python3 virtual environment package by running the command below:
Create folder for environments and change your working directory to it. To do so, run:
Create a virtual environment and give it a name which will best describe the environment purpose:
Actually, the command above create a directory with needed files. Patternodes 2 2 8 cm. To view them type:
The output must look like the one below:
To be able to use the newly created environment you must run:
After activating the environment you must see the environment name in brackets in front of your prefix. E.g.
To leave the environment just type the command below:
How to create simple python application within the virtual environment
After virtual environment is created we can create a simple application inside it and test if it works. Our application will output 'I am new to Python!' every time we run it. First of all we need to activate the environment or, if you want, enter inside the virtual environment. To do so, change your working directory to environments folder and run the command to activate the desired environment:
Create a file with .py extension via your favorite text editor and give it a name:
Add the following text in the file and save it:
Now every time you run your application with this command:
you'll see the output:
Read Also:
Python 3 comes already installed with Ubuntu 18.04 and it's very easy to update it to latest once there is a need. However, if you are using Ubuntu 18's minimal version you must install python manually and there are two ways to install it. One is using apt, which will install minimal packages of python3 and the other using source code which will install the full version of python 3.
