It's also important to note that using this, time will drift, depending on how long the command you're running takes to complete. If you're doing something more complicated, make sure that the interval is shorter than the time required for the command to finish, or else this might interfere with something in your script. The following one-liner runs the echo $(date) command every 5 seconds: Here, you need to replace command with the command to run, and X with the time interval in seconds (the number doesn't have to be an integer, but it can't be negative you can also specify minutes - 1m for example, hours - 1h for example, etc.).Įxample. Using sleep in a while loop to repeat a command every X secondsĪnother way of repeating a command every X seconds on Linux is to use a while loop with the sleep command: You might also like: How To Find Files Modified In The Last N Days Or Minutes Using find Check out its man page for more information. The watch command has a few options, like highlighting the differences between successive updates ( -differences / -d), beep if a command has a non-zero exit ( -beep / -b), and more.

The following command runs ps aux | grep firefox every 5 seconds: If the command contains pipes, quotes or other special characters, use single quotes, e.g.: 'command'.Įxample. X is the interval at which to run the command, in seconds (with 0.1 seconds being the lowest possible value).

Using watch to run a command every X seconds: This allows you to watch the program output change over time.

Watch can run a command repeatedly, displaying its output and errors (the first screenful). Using watch to run a command every X seconds This article explains how to repeat a command every X seconds on Linux, in 2 ways: using watch, and using sleep in a while loop (with a way to avoid time drift when using long-running commands).

Mac sleep command line