netselect-apt:tldr:c31f4
This command is a Linux shell command that uses the sudo command and runs the netselect-apt program with a variable called "${testing}".
The "sudo" command gives the user root privileges, allowing them to execute commands with administrative privileges.
"netselect-apt" is a program used in Debian-based Linux distributions to find the fastest Debian mirror server. It helps in selecting the optimal mirror for downloading packages from the apt package manager.
"${testing}" is a variable that is expected to hold a value representing a Debian repository, specifically the testing repository. The value of this variable would be passed as an argument to the netselect-apt program, which then uses it to determine the fastest mirror server for that repository.