sleep is good

My experience using bash is near zero, but I have been playing around with a couple of simple bash commands that I find pretty useful. The workhorse in these is the “sleep” command combined wth “while true; do”. The combo is incredibly simple, but I find uses for it all the time. Here are some examples of how I am using it:

Keep the SSH Alive Script

 while true; do
        sleep 900

This will do nothing more than print the date every 15 minutes. I find that it helps keep SSH tunnels open while waiting for results. They tend to just shut themselves off if they get bored.

Auto Updating Script

We can also package this same idea into a script that can be saved into a file and run externally. First, put the following into a plain text file

repo_url='<USER NAME>/<REPO NAME>'
while true; do
        git -C ~/source/ pull $repo_url $branch
        sleep 3600

To run this script, you first make it executable by running

chmod +x <FILE NAME>

If you run this script simply by calling its name in the terminal, it will automatically pull down from the HEAD branch on the given repo every hour. I find this very useful to run on some remote machines that I rarely make code on, but often run code on.