Commands for the wicked (109)

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list files recursively by size

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"

Tell what is encoded in a float, given its HEX bytes
It handles all possible combination of the hex bytes, including NaNs, Infinities, Normalized and Subnormal Numbers... $ This crazy DC stuff spent me a few days to write, optimize, polish and squeeze so that it works within the tight 255 character bound... $ You can modify it easily for other IEEE754 numbers, say, half, double, double-extended, quadruple $ (I hope someone will find this useful and submit more dc code to commandlinefu!)

Rotate all jpeg images in current folder, rename them to EXIF datetime and set files timestamp to EXIF datetime

Remote Serial connection redirected over network using SSH
Requires software found at: http://lpccomp.bc.ca/remserial/ Remote [A] (with physical serial port connected to device) $./remserial -d -p 23000 -s "115200 raw" /dev/ttyS0 & Local [B] (running the program that needs to connect to serial device) Create a SSH tunnel to the remote server: $ssh -N -L 23000:localhost:23000 [email protected] Use the locally tunnelled port to connect the local virtual serial port to the remote real physical port: $./remserial -d -r localhost -p 23000 -l /dev/remser1 /dev/ptmx & Example: Running minicom on machine B using serial /dev/remser1 will actually connect you to whatever device is plugged into machine A's serial port /dev/ttyS0.

Check if x509 certificate file and rsa private key match
A x509 certificate and a rsa key file have in common a parameter called modulus, it is a very long hexadecimal number. That value is unique for each certficate / key pair. The command allows to do the check of this pair of values in a script using a great feature of bash. "

rsync directory tree including only files that match a certain find result.
'-mtime -10' syncs only files newer 10 days (-mtime is just one example, use whatever find expressions you need) printf %P: File's name with the name of the command line argument under which it was found removed. this way, you can use any src directory, no need to cd into your src directory first. using \\0 in printf and a corresponding --from0 in rsync ensures that even filenames with newline characters work (thanks syssyphus for #3808). both, #1481 and #3808 just work if you either copy the current directory (.) , or the filesystem root (/), otherwise the output from find and the source dir from rsync just don't match. #7685 works with an arbitrary source directory.

List all databases in Postgres and their (byte/human) sizes, ordering by byte size descending
Get a listing of all of your databases in Postgres and their sizes, ordering by the largest size first. Requires that you give the -d parameter a valid database name that you can connect to.

for all flv files in a dir, grab the first frame and make a jpg.
This is handy for making screenshots of all your videos for referring to in your flv player.

Changing the terminal title to the last shell command
You can set the previous bash command as the terminal title by this command. Explanation: -trap assigns a command to execute at a given bash signal. -in the $BASH_COMMAND you find the last command -you can set the terminal title with the escape sequence: \e]0;this is the title\007 -to let the echo care about the backslashes give the -e to it Since trap is a built in bash command you find more informatin in 'man bash'for more Source: http://www.davidpashley.com/articles/xterm-titles-with-bash.html


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