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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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Maintained by Jon H.

Site originally by David Winterbottom (user root).

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

All commands from sorted by
Terminal - All commands - 12,388 results
rm -rf ~/.local/share/Trash/files/*
date -d @$(echo $((2 ** 31 - 1)))
2009-03-30 19:42:20
User: jnash
Functions: date echo


Some other notable dates that have passed:

date -d@1234567890 date -d@1000000000
alias rot13="tr '[A-Za-z]' '[N-ZA-Mn-za-m]'"
2009-03-30 19:08:49
User: penpen
Functions: alias
Tags: Linux unix

rot13 maps a..mn..z (A..MN..Z) to n..za..m (n..za..m) and so does this alias.

mkdir() { /bin/mkdir $@ && eval cd "\$$#"; }
alias l='ls -CFlash'
2009-03-30 17:11:31
Functions: alias

create a short alias for 'ls' with multi-column (-C), file type syntax additions (slashes after directories, @ for symlinks, etc... (-F), long format (-l), including hidden directories (all ./, ../, .svn, etc) (-a), show file-system blocks actually in use (-s), human readable file sizes (-h)

cat /var/log/secure | grep smtp | awk '{print $9}' | cut -f2 -d= | sort | uniq -c | sort -n | tail
2009-03-30 15:49:54
User: empulse
Functions: awk cat cut grep sort uniq

Searches /var/log/secure for smtp connections then lists these by number of connections made and hosts.

cat /var/log/secure | grep sshd | grep Failed | sed 's/invalid//' | sed 's/user//' | awk '{print $11}' | sort | uniq -c | sort -n
2009-03-30 15:48:24
User: empulse
Functions: awk cat grep sed sort sshd uniq

Searches the /var/log/secure log file for Failed and/or invalid user log in attempts.

whiptail --checklist "Simple checkbox menu" 11 35 5 tag item status repeat tags 1
2009-03-30 12:21:48
Tags: ncurses,

Not so much handy by itself, but very nice in shell scripts.

This makes you a handy ncurses based checklist. Much like terminal installers, just use the arrow keys and hit 'Space' to adjust the selections. Returns all selected tags as strings, with no newline at the end. So, your output will be something like:

"one" "two" "three" "four" "etc"

For those who prefer bash expansion over gratuitious typing:

whiptail --checklist "Simple checkbox menu" 12 35 3 $(echo {one,two,three,four}" '' 0"} )

Things to note:

The height must includes the outer border and padding: add 7 to however many items you want to show up at the same time.

If the status is 1, it will be selected by default. anything else, will be deselected.

du -xk | sort -n | tail -20
2009-03-30 11:37:43
User: dopeman
Functions: du sort tail

This command will tell you the 20 biggest directories starting from your working directory and skips directories on other filesystems. Useful for resolving disk space issues.

Printing portion of a big file
2009-03-30 11:08:38
User: acirulli
Tags: sed

If you need to print some portion of a huge file, let's say you want to print from line 200 to 300, you can use this command to print the line from LINE1 to LINE2 of file FILE.

pinfo date
2009-03-30 10:05:56
User: atoponce

The pinfo package makes info pages much more bearable. It is a ncurses-based POSIX utility for viewing info and man pages using lynx style keyboard shortcuts and rendering. Links are highlighted blue, the current location of your cursor is red. Navigating and searching are easy. Worth the install.

Convert UNIX time to human readable date
find ~/.thumbnails/ -type f -atime +30 -print0 | xargs -0 rm
2009-03-30 04:23:07
User: alperyilmaz
Functions: find xargs

By time thumbnail images in ~/thumbnails take up too much space, this command will help deleting old ones.

Find options explained:

-type f : find files only, not directories

-atime +30 : last accessed more than 30 days ago

alias up="cd .."; alias upp="cd ../.."; alias uppp="cd ../../.."; alias upppp="cd ../../../.."; alias uppppp="cd ../../../../.."
acpi -tc
watch -tn1 'bc<<<"`date -d'\''friday 21:00'\'' +%s`-`date +%s`"|perl -ne'\''@p=gmtime($_);printf("%dd %02d:%02d:%02d\n",@p[7,2,1,0]);'\'
2009-03-29 19:53:36
User: penpen
Functions: perl watch
Tags: Linux unix date

An improved version of http://www.commandlinefu.com/commands/view/1772/simple-countdown-from-a-given-date that uses Perl to pretty-print the output. Note that the GNU-style '--no-title' option has been replaced by its one-letter counterpart '-t'.

svn rm `svn status | grep "\!" | cut -c 8-`
2009-03-29 13:28:55
User: benschw
Functions: cut grep rm
Tags: svn

If (when) you forget to "svn rm" files from your repository, use this to let your repository know you want those files gone. Of course this works with adding and reverting too.

find /home/user/doc/ -type d -printf "mkdir -vp '/home/user/Dropbox%p'\n" -o -type f -printf "ln -vs '%p' '/home/user/Dropbox%p'\n" | sh
2009-03-29 09:25:12
User: jnash
Functions: find

Extremely useful to maintain backups if you're using Dropbox. This mirrors the entire directory structure and places symlinks in each to the original file. Instead of copying over the data again to the ~/Dropbox folder creating a symbolic link tree is much more sensible in terms of space usage.

This has to be supplemented by another script that removes dead symlinks in the Dropbox folder which point to files that have been moved/removed.

find -L ./ -type l -delete

And then removing empty directories

find ./ -type d -exec rmdir 2>/dev/null {} \;

**Actually after some finding I found lndir which creates symbolic trees but it wasn't in the Arch repos so.. ;)

yelp info:foo
yelp man:foo
2009-03-29 07:13:44
User: renich
Tags: man yelp

A great way of viewing some man page while using gnome.

sftp -s "sudo /usr/lib/sftp-server" user@host
2009-03-29 07:02:58
User: mrtheplague
Functions: sftp

This requires that your sudo not prompt for a password, as sftp cannot allocate the terminal necessary to ask.

watch --no-title -d -n 1 'echo `date -d "next Thursday" +%s` "-" `date +%s` | bc -l'
2009-03-29 06:53:09
User: jnash
Functions: bc watch

Might be more useful if you were able to print it in Days HH:MM:SS format as:

perl -e '@p=gmtime(234234);printf("%d Days %02d:%02d:%02ds\n",@p[7,2,1,0]);'

But I'm not exactly sure how to replace the 234234 with the output of the countdown time. (Having some problems with nested quoting/command substitution). Help would be appreciated :)

dscacheutil -flushcache
< /path/to/file.txt grep foo
2009-03-29 02:43:40
User: atoponce
Functions: grep

Several times, I find myself hitting my up arrow, and changing the search term. Unfortunately, I find myself wasting too much time typing:

grep kernel /var/log/messages

Redirecting STDIN allows me to put the search term at the end so I less cursor movement to change what I'm searching for:

< /var/log/messages grep kernel

If you're using the emacs keyboard binding, then after you press your up arrow, press CTRL+w to erase the word.

If this has already been submitted, I couldn't find it with the search utility.