$ curl cheat.sh/

# update-alternatives
# A convenient tool for maintaining symbolic links to determine default commands.
# More information: <https://manned.org/update-alternatives>.

# Add a symbolic link:
sudo update-alternatives --install path/to/symlink command_name path/to/command_binary priority

# Configure a symbolic link for `java`:
sudo update-alternatives --config java

# Remove a symbolic link:
sudo update-alternatives --remove java /opt/java/jdk1.8.0_102/bin/java

# Display information about a specified command:
update-alternatives --display java

# Display all commands and their current selection:
update-alternatives --get-selections

$

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