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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

do something else while waiting for an event, such as reboot

Terminal - do something else while waiting for an event, such as reboot
until (ssh [email protected] 2> /dev/null); do date; sleep 15; done
2011-03-08 08:42:12
User: greggster
Functions: sleep ssh
do something else while waiting for an event, such as reboot

until (ssh [email protected] 2> /dev/null); do date; sleep 15; done

In this case will execute "date" then "sleep 15" until we are able to ssh into server, such as after a reboot

Could also be like:

until ( ping 1> /dev/null); do echo "server is down"; sleep 15; done


There are 15 alternatives - vote for the best!

Terminal - Alternatives

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What others think

Not that it makes any significant difference in this case, but those parentheses around the commands are not necessary. Also, that ping command will go on pinging forever unless you give it a count with the -c option, and as far as I'm aware, GNU ping only sets an error code if it also fails to transmit any packets. Which means, as long as ping's able to transmit its echo requests, 'echo "server is down"; sleep 15' won't run even if ping doesn't receive any responses.

Comment by eightmillion 293 weeks and 3 days ago

yes the ping will need a -c arg - else it will as you say ping forever...

Comment by greggster 216 weeks and 2 days ago

Your point of view

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