I want to know about different update and upgrade commands as follows:
For new users of Ubuntu and using the command-line, which of these is used and when? In brief, help me to understand the use of the above commands.
APT (Advanced Packaging Tool) is a management system for software packages. Usually used as root/sudo user. The usual command is
apt-get, but with Ubuntu 14.04, there's also the
apttool: What is the difference between apt and apt-get?
sudo apt-get update:
/etc/apt/preferencesor adding/removing repositories, you have to run this command to make
aptaware of your changes.
Run this command periodically to make sure your source list is up-to-date. This is the equivalent of "Reload" in Synaptic.
apt updateis equivalent.
sudo apt-get upgrade:
This command upgrades all installed packages. This is the equivalent of "Mark all upgrades" in Synaptic.
sudo apt-get dist-upgrade:
apt-get dist-upgradedoes not perform distribution upgrade. visit this for upgrading.
apt full-upgradeis equivalent.
sudo apt-get dselect-upgrade:
dpkgin order to get information through
-d, --devel-releaseto check if upgrading to the latest devel release is possible
Note: All Information is provided with use of manpages, and community help as a reference/source.