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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

The Chronic: run a command every N seconds in the background

Terminal - The Chronic: run a command every N seconds in the background
chronic () { t=$1; shift; while true; do $@; sleep $t; done & }
2009-06-13 05:57:54
User: rhythmx
Functions: sleep
The Chronic: run a command every N seconds in the background

Chronic Bash function:

chronic 3600 time # Print the time in your shell every hour chronic 60 updatedb > /dev/null # update slocate every minute

Note: use 'jobs' to list background tasks and fg/bg to take control of them.


There is 1 alternative - vote for the best!

Terminal - Alternatives

Know a better way?

If you can do better, submit your command here.

What others think

Crontab/at commands would be better, if you have the rights to use them.

Comment by jxy 396 weeks and 2 days ago

I use while true to make neverending loops with while.

Comment by b2e 396 weeks and 2 days ago

In case you want it as a foreground process, this is exactly what 'watch' is for. watch repeatedly executes a command at a user-specified interval and displays the results. I agree with the others, if you make it a background process, you might as well automate it with cron.

Comment by bwoodacre 396 weeks and 2 days ago

Doh.. totally forgot about `watch'. Anyway running things in a term as opposed to cron can have distinct advantages. The command will only ever run as long as your session, and you'll get all of your environment vars automatically (e.g. DISPLAY).

I just pasted that from my new shiny .xinitrc for fluxbox, it watches for mtime updates to my wallpaper JPEG and automatically updates the rootbg when it changes.

Comment by rhythmx 396 weeks and 2 days ago

Could use incron for that purpose rhythmx.

Comment by DaveQB 396 weeks ago

you can avoid while true:

chronic () { t=$1; shift; while sleep $t; do $@; done & }
Comment by glaudiston 337 weeks ago

or better, if you want it, do not need to do a function, use while directly:

while sleep ; do ; done &

Comment by glaudiston 336 weeks and 6 days ago

the command above was modified by site:

while sleep <you time>; do <your command>; done;
Comment by glaudiston 336 weeks and 6 days ago

Your point of view

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