Commands by psykotron

Commands by psykotron (4)

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Find common groups between two users
This is sample output - yours may be different.
2

grep -xFf <(groups user1|cut -f3- -d\ |sed 's/ /\n/g') <(groups user2|cut -f3- -d\ |sed 's/ /\n/g')

psykotron · 2015-03-04 18:23:59 1
Figure out what shell you're running

short, sweet, and works after sudoing a new shell. Show Sample Output
This is sample output - yours may be different.
```
  PID TTY          TIME CMD
 9155 pts/0    00:00:00 bash
```
3

ps -p $$

psykotron · 2011-02-05 16:22:17 0
Extract tarball from internet without local saving
This is sample output - yours may be different.
8

curl http://example.com/a.gz | tar xz

psykotron · 2009-12-20 18:47:49 0
Another Matrix Style Implementation

A bit different from some of the other submissions. Has bold and uses all c printable characters. Change the bs=value to speed up and increase the sizes of the bold and non-bold strings.
This is sample output - yours may be different.
5

echo -ne "\e[32m" ; while true ; do echo -ne "\e[$(($RANDOM % 2 + 1))m" ; tr -c "[:print:]" " " < /dev/urandom | dd count=1 bs=50 2> /dev/null ; done

psykotron · 2009-12-19 19:05:04 1

What's this?

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Get the SAN (subjectAltName) of a site's certificate.

Based on http://stackoverflow.com/questions/13127352/checking-alternative-names-for-a-san-ssl-cert Replace "facebook.com" with the desired hostname.

Sync the date of one server to that of another.

(Useful when firewalls prevent you from using NTP.)

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 apps that use internet connection at the moment. (Multi-Language)

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" }

prevents replace an existing file by mistake

Use set +o noclobber and you will be able to replace files again

Top 10 Memory Processes

It displays the top 10 processes sorted by memory usage

Show all LISTENing and open server connections, with port number and process name/pid

Display or use a random file from current directory via a small bash one-liner

An other way to run it ( playing a random file ending with avi, flv or mpeg ) from a specified dir and a specified type of extension : making MOVIE array with a glob : $ MOVIE=( /PATH/TO/MY/FAVORITE/MOVIES/*.{avi,flv,mpeg} ) playing the random file from a random key from the array $ mplayer ${MOVIE[ RANDOM % ( ${#i[@]} + 1 ) ]]} I use only globs and a bash array. I use GNU bash, version 3.2.48

list block devices

Shows all block devices in a tree with descruptions of what they are.

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