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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

sort the contents of a text file in place.

Terminal - sort the contents of a text file in place.
sort -g -o list.txt{,}
2011-11-15 19:59:28
User: jambino
Functions: sort
sort the contents of a text file in place.

sorts the contents of a file without the need for a second file to take the sorted output.

This was previously entered as `sort -g list.txt -o $_` but as others have pointed out the $_ references the previous command. so this would've worked had that been the second part of a command joined with && like:

cat list.txt && sort -g list.txt -o $_

The user below me Robin had the most correct command.


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

The $_ shell variable expands to the last argument to the previous command. You could use brace expansion, like this:

sort -g -o list.txt{,}

or history expansion, like this:

sort -g -o list.txt !#:$


sort -g list.txt -o !#:2
Comment by Robin 263 weeks and 4 days ago

Since "$_" expands to the last argument of the previous command, it will fail if list.txt is not referenced previously

A better approach is to use history reference "!^" to the first argument (non-option) of the current command:

sort -g list.txt -o !^
Comment by caruccio 222 weeks and 6 days ago

Your point of view

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