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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

run a command whenever a file is touched

Terminal - run a command whenever a file is touched
ontouchdo(){ while :; do a=$(stat -c%Y "$1"); [ "$b" != "$a" ] && b="$a" && sh -c "$2"; sleep 1; done }
2010-10-22 23:25:12
User: putnamhill
Functions: sh sleep stat
run a command whenever a file is touched

This is useful if you'd like to see the output of a script while you edit it. Each time you save the file the command is executed. I thought for sure something like this already exists - and it probably does. I'm on an older system and tend to be missing some useful things.


ontouchdo yourscript 'clear; yourscript somefiletoparse'

Edit yourscript in a separate window and see new results each time you save.

ontouchdo crufty.html 'clear; xmllint --noout crufty.html 2>&1 | head'

Keep editing krufty.html until the xmllint window is empty.

Note: Mac/bsd users should use stat -f%m. If you don't have stat, you can use perl -e '$f=shift; @s=stat($f); print "$s[9]\n";' $1


There is 1 alternative - vote for the best!

Terminal - Alternatives
while true; do inotifywait -r -e MODIFY dir/ && make; done;
2010-06-04 17:07:03
User: fain182

Uses inotifywait from inotify-tools ( http://wiki.github.com/rvoicilas/inotify-tools/ ), that is compatible only with linux.

Usefull when you work with files that have to be compiled.. latex, haml, c..

while inotifywait -e modify /tmp/myfile; do firefox; done
inotifywait -mrq -e CREATE --format %w%f /path/to/dir | while read FILE; do chmod g=u "$FILE"; done
2010-10-21 23:36:02
User: dooblem
Functions: chmod read

Listens for events in the directory. Each created file is displayed on stdout. Then each fileline is read by the loop and a command is run.

This can be used to force permissions in a directory, as an alternative for umask.

More details:


while inotifywait -r -e MODIFY dir/; do make; done;
runonchange () { local cmd=( "$@" ) ; while inotifywait --exclude '.*\.swp' -qqre close_write,move,create,delete $1 ; do "${cmd[@]:1}" ; done ; }
2015-04-08 17:42:03
User: funollet


runonchange /etc/nginx nginx -t

Ignores vim temp files. Depends on 'inotify-tools' for monitoring of file changes. Alternative to tools like 'entr', 'watchr'.

Know a better way?

If you can do better, submit your command here.

What others think

Nice! Was this inspired by the ever useful onlogdo script? http://www.sigterm.net/projects/onlogdo

Comment by hackerb9 313 weeks and 5 days ago


Added to my personal collection of usefull oneliners. I also added 2> /dev/null after the stat command, so I can do; ontouchdo nonexistingfile 'date', to see when that file gets created..

Comment by xeor 313 weeks and 5 days ago

@hackerb9 I'm not familiar with onlogdo, but I did have the funny feeling I was reinventing the wheel. ;) I'll check it out.

@xeor Good idea! I'll try it on my copy.

Comment by putnamhill 313 weeks and 5 days ago

Your point of view

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