特許これっぽい?><
https://pdfpiw.uspto.gov/.piw?PageNum=0&docid=10807006&IDKey=DF8030302054%0D%0A&HomeUrl=http%3A%2F%2Fpatft.uspto.gov%2Fnetacgi%2Fnph-Parser%3FSect1%3DPTO2%2526Sect2%3DHITOFF%2526u%3D%25252Fnetahtml%25252FPTO%25252Fsearch-adv.htm%2526r%3D97%2526f%3DG%2526l%3D50%2526d%3DPTXT%2526s1%3Damazon.ASNM.%2526p%3D2%2526OS%3DAN%2Famazon%2526RS%3DAN%2Famazon
思考の /dev/null