Here is the query from my colleague again. What if I want to keep the last 5 hour modified file in the directory and move/copy the rest of the files.

you should tell your colleague to stop changing the requirements. things are now complicated enough that a perl solution would be better than a shell solution. see the other responses in the thread for pointers in that direction.

hi zengargoyle, Sorry for the irritating and complexity request. I will look at other responses in the thread for pointers. At least I knew that to keep track last modified file base on time will be good to use perl script. Million Thanks. rgds, hyliau