Commands by johnraff (5)

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Which fonts are installed?
See all fonts installed in your system

Find number of computers in domain, OU, etc .

m4a to mp3 conversion with ffmpeg and lame
A batch file version of the same command would be: for f in *.m4a; do ffmpeg -i "$f" -acodec libmp3lame -ab 256k "${f%.m4a}.mp3"; done

Don't spam root. Log your cronjob output to syslog
This command will log the output of your simple cronjobs to syslog, and syslog will take it from there. Works great for monitoring scripts which only produce simple output. Advantages: * This can be used by regular users, without modifying system files like /etc/syslog.conf * Reduce cron spam to root@localhost (Please stop spaming the sysadmins) * Uses common tools like syslog (and logrotate) so that you don't need to maintain yet another krufty logfile. * Still ensures that the output is logged somewhere, for posterity. Perhaps it's stored the secure, central syslog server, for example. * Seems to work fine on Ubuntu, CentOS, FreeBSD & MacOSX

Calculate N!
Same as the seq/bc solution but without bc.

Grep inside Vim and navigate results
Will search for the given pattern and build a list of occurrences. Then you can use :copen and :cclose to toggle the list. When browsing the list, ENTER will take you to that line in the file.

Copy text to the clipboard
Great for little scripts that dig up obscure info that you are going to have to paste into another app anyway.

Mac OS X: remove extra languages to save over 3 GB of space.
This will get the job done in the most efficient way - spawning only one `rm` process. "On-the-fly" find data is displayed through `tee` and you should have plenty of time to ctrl-c if needed before it's too late. You may need to re-run this after major Software Updates. To leave more languages in, add more ``-and \! -iname "lang*"'' statements: $ sudo find / -iname "*.lproj" -and \! -iname "en*" -and \! -iname "spanish*" -print0 | tee /dev/stderr | sudo xargs -0 rm -rfv **Edit: note the 2nd sudo near the end of the pipeline - this is necessary.

Protect your eye
Redshift will adjust the color temperature and protects eye at night -b : will adjust the brightness

Wait for file to stop changing
Here's a way to wait for a file (a download, a logfile, etc) to stop changing, then do something. As written it will just return to the prompt, but you could add a "; echo DONE" or whatever at the end. This just compares the full output of "ls" every 10 seconds, and keeps going as long as that output has changed since the last interval. If the file is being appended to, the size will change, and if it's being modified without growing, the timestamp from the "--full-time" option will have changed. The output of just "ls -l" isn't sufficient since by default it doesn't show seconds, just minutes. Waiting for a file to stop changing is not a very elegant or reliable way to measure that some process is finished - if you know the process ID there are much better ways. This method will also give a false positive if the changes to the target file are delayed longer than the sleep interval for any reason (network timeouts, etc). But sometimes the process that is writing the file doesn't exit, rather it continues on doing something else, so this approach can be useful if you understand its limitations.


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