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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

Carriage return for reprinting on the same line

Terminal - Carriage return for reprinting on the same line
while true; do echo -ne "$(date)\r"; sleep 1; done
2009-11-17 22:45:37
User: polaco
Functions: echo sleep
Carriage return for reprinting on the same line

The above code is just an example of printing on the same line, hit Ctrl + C to stop

When using echo -ne "something\r", echo will:

- print "something"

- dont print a new line (-n)

- interpret \r as carriage return, going back to the start of the line (-e)

Remember to print some white spaces after the output if your command will print lines of different sizes, mainly if one line will be smaller than the previous

Edit from reading comments: You can achieve the same effect using printf (more standardized than echo): while true; do printf "%-80s\r" "$(date)"; sleep 1; done


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

Using terminfo here is better, IMO. Just using '\r' will not clear out junk characters on the end left by previous iterations of the loop.

el1=$(tput el1); while true; do echo -ne "${el1}\r$(ps -eo %cpu,comm --sort %cpu|tail -1)"; sleep 1; done
Comment by arcege 368 weeks and 2 days ago

Note that there are various implementations of the echo command, and not all of them support backslash codes. Also, many shells have a builtin echo command that behaves differently from /bin/echo.

Therefore it is better to use printf which is standardized, so

echo -ne $(date)


printf "%s\r" $(date)

You can also easily get rid of the junk character problem that arcege mentioned:

printf "%-79\r" $(date)

Explanation: The "-" modifier will print the argument left-justified and overwrite the rest of the line with spaces. This assumes at least 80 characters per line, which should be more sufficient because the output from the date command is much shorter.

Comment by inof 368 weeks and 1 day ago

That should be:

printf "%s\r" "$(date)"
Comment by cfajohnson 368 weeks ago

Thanks for the additions guys, i edited the command

Comment by polaco 367 weeks and 4 days ago

Your point of view

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