Commands tagged regex (60)

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OpenDns IP update via curl
Your IP is resolved by OpenDns Server (like a caller ID telephone, every server knows who is calling ;-) Change user:password by yours Be Happy

move you up one directory quickly
In bash, this turns on auto cd. If a command is just a directory name, it cd's into that directory.

a function to find the fastest DNS server
http://public-dns.info gives a list of online dns servers. you need to change the country in url (br in this url) with your country code. this command need some time to ping all IP in list.

dstat- this command is powerful one to monitor system activity . It has combined the power of vmstat,iostat,mpstat,df,free,sar .
As mentioned in the summery that it is a powerful command to monitor system activity in great way. It has got the power of vmstat,iostat,mpstat,df,free and sar.Instead of firing each single command separately ,one can fire one single command to get all the info at once.But there is a way to get the individual information too. Please see the man page . You can get it from here : http://dag.wieers.com/home-made/dstat/

Read and write to TCP or UDP sockets with common bash tools
Ever needed to test firewalls but didn't have netcat, telnet or even FTP? Enter /dev/tcp, your new best friend. /dev/tcp/(hostname)/(port) is a bash builtin that bash can use to open connections to TCP and UDP ports. This one-liner opens a connection on a port to a server and lets you read and write to it from the terminal. How it works: First, exec sets up a redirect for /dev/tcp/$server/$port to file descriptor 5. Then, as per some excellent feedback from @flatcap, we launch a redirect from file descriptor 5 to STDOUT and send that to the background (which is what causes the PID to be printed when the commands are run), and then redirect STDIN to file descriptor 5 with the second cat. Finally, when the second cat dies (the connection is closed), we clean up the file descriptor with 'exec 5>&-'. It can be used to test FTP, HTTP, NTP, or can connect to netcat listening on a port (makes for a simple chat client!) Replace /tcp/ with /udp/ to use UDP instead.

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Show most common words in filenames
I'm sure there's a more elegant sed version for the tr + grep section.

Play musical notes from octave of middle C
Are there any creative pieces of music that can be created using beep and the shell? I'd love to hear it!

Spy audio, it only records if detects a sound or noise
It find out the mic recording level at the moment of run the command and if a noise level is higher it starts to record an mp3 file. The resulting file will have only the sounds not the silences.

How long has this disk been powered on


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