Commands by kofrezo (1)

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Making scripts runs on backgourd and logging output
Save all output to a log.

Show changed files, ignoring permission, date and whitespace changes
Only shows files with actual changes to text (excluding whitespace). Useful if you've messed up permissions or transferred in files from windows or something like that, so that you can get a list of changed files, and clean up the rest.

Check which modules your PHP is using

Send a binary file as an attachment to an email
The uuencode utility will encode your file so that it can be sent as an attachment to an email. It is part of the sharutils package in RHEL/CentOS/Fedora.

Convert YAML to JSON
* Output is jq compatible * Output is single lines - unix compatible * Multiple files supported

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

List bash functions defined in .bash_profile or .bashrc
http://stackoverflow.com/questions/2625783/listing-defined-functions-in-bash#2627461

resize all JPG images in folder and create new images (w/o overwriting)
Convert all jpegs in the current directory into ~1024*768 pixels and ~ 150 KBytes jpegs

grep tab chars
mixing tabs and spaces for indentation in python would confuse the python interpreter, to avoid that, check if the file has any tab based indentation. "^V" => denotes press control + v and press tab within quotes. $ cat improper_indent.py class Tux(object): print "Hello world.." $ grep " " improper_indent.py print "Hello world.."

Test your total disk IO capacity, regardless of caching, to find out how fast the TRUE speed of your disks are
Depending on the speed of you system, amount of RAM, and amount of free disk space, you can find out practically how fast your disks really are. When it completes, take the number of MB copied, and divide by the line showing the "real" number of seconds. In the sample output, the cached value shows a write speed of 178MB/s, which is unrealistic, while the calculated value using the output and the number of seconds shows it to be more like 35MB/s, which is feasible.


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