From https://www.gnu.org/software/bash/manual/html_node/Redirections.htmlBash handles several filenames specially when they are used in redirections, as described  in the following table:/dev/fd/fd If fd is a valid integer, file descriptor fd is  duplicated./dev/stdin File descriptor 0 is duplicated./dev/stdout File descriptor 1 is duplicated./dev/stderr File descriptor 2 is duplicated.what does duplicated mean here? Can you give some examples?
Duplication of file descriptors in redirection
bash;shell;io redirection;file descriptors