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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 all Windows services on the command line
On Windows 2000 or later, this command will give a listing of all the registered Windows services. You can then know what the name of a command is in order to start and stop it. e.g. $ sc start Apache2.2 or $ net start Apache2.2 Please note that sc will allow the SERVICE_NAME only, while net will allow both SERVICE_NAME and DISPLAY_NAME. Note that the space between the = and the next word are important. Not very unixy, that. http://www.ss64.com/nt/sc.html http://www.ss64.com/nt/net_service.html http://technet.microsoft.com/en-us/library/bb490995.aspx

Numeric zero padding file rename
rename file name with fixed length nomeric format pattern

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

convert uppercase files to lowercase files

Convert mp3/wav file to asterisk ulaw for music on hold (moh)

Increase SCT of external USB disk enclosure to one hour.
So I had this 2TB Seagate external disk/USB enclosure which by default would spin-down its internal drive (it enters a standby mode) after four minutes of inactivity.. Spinning-up the inactive drive was an annoying delay when accessing files and also it severely interfered with NFS.. SCT stands for "Standby Condition Timer". To completely disable SCT: $ sdparm --clear STANDBY -6 /dev/sdb To return to original (default) SCT settings: $ sdparm -D -p 0x1a -6 /dev/sdb To verify the settings (before and after): $ sdparm -a /dev/sdb No need for vendor-provided MSWIN tools, etc.

What is my ip?

Efficient count files in directory (no recursion)
$ time perl -e 'if(opendir D,"."){@a=readdir D;print $#a - 1,"\n"}' 205413 real 0m0.497s user 0m0.220s sys 0m0.268s $ time { ls |wc -l; } 205413 real 0m3.776s user 0m3.340s sys 0m0.424s ********* ** EDIT: turns out this perl liner is mostly masturbation. this is slightly faster: $ find . -maxdepth 1 | wc -l sh-3.2$ time { find . -maxdepth 1|wc -l; } 205414 real 0m0.456s user 0m0.116s sys 0m0.328s ** EDIT: now a slightly faster perl version $ perl -e 'if(opendir D,"."){++$c foreach readdir D}print $c-1,"\n"' sh-3.2$ time perl -e 'if(opendir D,"."){++$c foreach readdir D}print $c-1,"\n"' 205414 real 0m0.415s user 0m0.176s sys 0m0.232s

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


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