hello, please help. i use this command (ls dirA |cut -d. -f1 |uniq) to do listing on a list of files under dirA. files name example: A20010101.1 A20010101.2 A20010102.1 A20010103.1 then, my command give me a result like this: A20010101 A20010102 A20010103 problem is, i want to compare the list of result with dirB with result such as: A20010101 A20010105 A20010106 A20010107 if i want to know whether dirA & dirB got same result(either line), then it will echo something to let me know. for the echo is no problem at all.problem is i do not know how to compare. i already try to use for-do-done, grep, ls,...(etc);still cannot.

Not sure, but if 2 things exist/work then the following should work, dirB must already exist and diff can accept piped inputs: ls dirA |cut -d. -f1 |uniq | diff dirB If not then you will have to do this: ls dirA | cut -d. -f1 | uniq > dirA; diff dirA dirB If there is no difference, nothing is returned, if there is a differnce you are usually returned a cryptic set of differnces which includes ed/vi instructions on how to make the files match. Hope this helps, good luck.