Commands by andykazmaier (1)

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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"

Show what PID is listening on port 80 on Linux

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" }

Show complete URL in netstat output
This takes all of the tab spaces, and uses column to put them into the appropriately sized table.

convert ascii string to hex
Even adds a newline.

The simplest way to transport information over a network
Einstein's razor: As simple as possible, but not simpler. On the destination machine netcat listens on any port (1234 in the example) and sends anything it receives into a file or pipe. On the source machine a separate netcat takes input from a file or pipe and sends it over the network to the listener. This is great between machines on a LAN where you don't care about authentication, encryption, or compression and I would recommend it for being simpler than anything else in this situation. Over the internet you should use something with better security.

Define a quick calculator function
POSIX compliant arithmetic evaluation. = 10*2+3

Extract all of the files on an RPM on a non-RPM *nix

Create multiple subfolders in one command.
Instead of typing separate commands to create various subfolders, we can create multiple subfolders by listing them between brackets and separated by commas.

List of computers not logged into in more than four weeks

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