watch - watch a program with update intervals
watch [-n] seconds program [ args ... ]
watch is a curses(3X) based program that allowsyou to watch a program as it changes. By default, itupdates itself every 2 seconds. You can specify the numberof seconds with the -n option. The curses packages allowsfor quick updating of the screen through cursoroptimization. The program will end with a keyboardinterrupt, which will leave the screen in avalid yet cleared state.
try:
On BSD:
watch -n 1 ps u
On System V:
watch -n 1 ps -f