Update the pacman mirror list using reflector.
The available commands are backup and update. The backup command will copy the mirrorlist file to mirrorlist.backup. The update command will map the configuration to a reflector command, then run that command.
A sample configuration file is included in /etc/pacmirror/pacmirror.conf.sample. This should be copied to /etc/pacmirror/pacmirror.conf and edited to your liking. You may also specify a configuration file using the --conf or -c parameter. The reflector section maps directly to reflector command-line options, so view the documentation for reflector to see what each option will do. The pacmirror section includes some options for pacmirror. These options should be self-documenting, or commented where appropriate.