Commands by thesuperjason (3)

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Remove executable bit from all files in the current directory recursively, excluding other directories
Useful if you have copied files from an OS without a permission structure (for example, DOS) and you need to disable all executable files but want to be able to descend into your directories.

invoke MATLAB functions from command line
`-r script.m` also possible

continuously print string as if being entered from the keyboard
Cycles continuously through a string printing each character with a random delay less than 1 second. First parameter is min, 2nd is max. Example: 1 3 means sleep random .1 to .3. Experiment with different values. The 3rd parameter is the string. The sleep will help with battery life/power consumption. $ cycle 1 3 $(openssl rand 100 | xxd -p) Fans of "The Shining" might get a kick out of this: $ cycle 1 4 ' All work and no play makes Jack a dull boy.'

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"

Transfer large files/directories with no overhead over the network
This invokes tar on the remote machine and pipes the resulting tarfile over the network using ssh and is saved on the local machine. This is useful for making a one-off backup of a directory tree with zero storage overhead on the source. Variations on this include using compression on the source by using 'tar cfvp' or compression at the destination via $ ssh user@host "cd dir; tar cfp - *" | gzip - > file.tar.gz

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Schedule a script or command in x num hours, silently run in the background even if logged out
This is helpful for shell scripts, I use it in my custom php install script to schedule to delete the build files in 3 hours, as the php install script is completely automated and is made to run slow. Does require at, which some environments without crontab still do have. You can add as many commands to the at you want. Here's how I delete them in case the script gets killed. (trapped) atq |awk '{print $1}'|xargs -iJ atrm J &>/dev/null

Compression formats Benchmark
See: http://imgur.com/JgjK2.png for example. Do some serious benchmarking from the commandline. This will write to a file with the time it took to compress n bytes to the file (increasing by 1). Run: $ gnuplot -persist

Print a list of all hardlinks in the working directory, recursively
libpurple likes to hardlink files repeatedly. To ignore libpurple, use sed: | sed '/\.\/\.purple/d'

Grabs a random image from "~/wallpapers" and sets as the background
don't bother spawning a bc process or counting the number of options, just pick a random one. 'sort -R' sorts randomly, so pick the top one.


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