?????????????"|"?? ??????????????????(stdout)?? ???????????????????(stdin)??.
??????????(filter)?? ????????????????????????.
???????????:
????sort: ????;
????uniq?? UNIQue?? ??????????е?????; ????"-d"?? ????????????;
????wc?? ???????(Word Count); ????"-l"?? ??????;
????grep?? ?????????? Global Regular Expression Print?? ?????????????;
???????:

????head?? ??????????漸?У? ???10??; ????"-n"?? ???????;
????tail?? ?????????β???У? ???10??; ????"-n"?? ???????;"-f"?? ??(real-time)?????????β???.
????tee?? ??????????(stdin)?? ??????????????(stdout)?????(file)??;