yes prints the command line arguments, separated by spaces and followed by a newline, forever until it is killed. If no arguments are given, it prints ‘y’ followed by a newline forever until killed.
Upon a write error, yes exits with status ‘1’.
The only options are a lone --help or --version. To output an argument that begins with ‘-’, precede it with --, e.g., ‘yes -- --help’. See Common options.