that's the one, from the readme: "If stdout is not a terminal the selected field will be written to stdout and exit without invoking the yank command" Could be

that's the one, from the readme: "If stdout is not a terminal the selected field will be written to stdout and exit without invoking the yank command" Could be clearer, basically it means that if it's part of a pipe, it's going to print to stdout instead of copying to the clipboard