how to redirect the growing contents of log file to another file in unix

how to redirect the growing contents of log file to another file in unix

Do you mean leaving the file open?

There is a way but I dont see any gain since you will have both files...

What were you thinking of? redirect then zero the file?

Do you want to do something like this?

tail -f the_log_file > new_file

Both log files will continue to grow.