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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"

Find out how old a web page is
I used to use the Firefox "View page info" feature a lot to determine how stale the web page I was looking at was. Now that I use mostly Chrome I miss that feature, so here is a command line alternative using wget. The -S says to display the server response, the --spider says to not download any files/pages, just fetch the header. The output goes to stderr, so to grep it you use 2>&1 to combine the stderr stream with stdout, the pipe that to grep for Last-Modified. You can use curl instead if you have it installed, like this: $ curl --head -s http://osswin.sourceforge.net | grep Mod

Show me just the ip address
Sometimes it's useful to output just the ip address. Or some other information, changing the "ipv4.addresses" in command. The power of awk! Show all possible "greps" with $ nmcli connection show [yourInterfaceNameHere]

Alert on Mac when server is up
When run on a mac, this command will bring up a dialog box in the Terminal when server HOSTNAME first responds to a ping.

find out which directory uses most inodes - list total sum of directoryname existing on filesystem

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

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"

Not a kismet replacement...
If you're like some individuals who rely on ndiswrapper and cannot use kismet, this command may be of service. watch -n .5 "iwlist wlan0 scan | egrep 'ESSID|Encryption'" Or... watch -n .5 "iwlist wlan0 scan | egrep 'ESSID|Encryption' | egrep 'linksys'" :-) Hopefully you'll find some dd-wrt compatible routers.

Backup of a partition
Clone a partion with tar.

Auto download Ubuntu 10.04 LTS with super fast zsync
Need to have rc iso pre-downloaded before running command.


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