The 'tee' Command

Sometimes you don't see an old, good thing, until you really need them.

tee is Linux shell command using which you can redirect a program's output to the screen as the same time dumping it on a file.

Usage:

$ < program> | tee < output_file>

If it is your own program, make sure that it flushes the output time to time if you want to readily see the output on the screen.