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list files recursively by size

count the number of specific characters in a file or text stream
In this example, the command will recursively find files (-type f) under /some/path, where the path ends in .mp3, case insensitive (-iregex). It will then output a single line of output (-print0), with results terminated by a the null character (octal 000). Suitable for piping to xargs -0. This type of output avoids issues with garbage in paths, like unclosed quotes. The tr command then strips away everything but the null chars, finally piping to wc -c, to get a character count. I have found this very useful, to verify one is getting the right number of before you actually process the results through xargs or similar. Yes, one can issue the find without the -print0 and use wc -l, however if you want to be 1000% sure your find command is giving you the expected number of results, this is a simple way to check. The approach can be made in to a function and then included in .bashrc or similar. e.g. $ count_chars() { tr -d -c "$1" | wc -c; } In this form it provides a versatile character counter of text streams :)

Generate a 18 character password, print the password and sha512 salted hash
Generate a 18 character password from character set a-zA-Z0-9 from /dev/urandom, pipe the output to Python which prints the password on standard out and in crypt sha512 form.

Update all packages installed via homebrew
As of March 7, 2012: $ brew update - downloads upgraded formulas $ brew upgrade [FORMULA...] - upgrades the specified formulas $ brew outdated - lists outdated installations Note updating all packages may take an excruciatingly long time. You might consider a discriminating approach: run `brew outdated` and select specific packages needing an upgrade. For more information see homebrew's git repository: https://github.com/mxcl/homebrew

nmap IP block and autogenerate comprehensive Nagios service checks
More info here: http://nagioswiki.com/wiki/index.php/Autocreating_Nagios_Configuration_with_Nmap_and_Nmap2Nagios.pl

Tweet from Terminal to twitter !
Tweeting from terminal to twitter accounts..

Display the inodes number of /

Rename files in batch

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

perl insert character on the first line on your file


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