Commands by nesses (3)

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Remove empty directories
It only works in zsh

Sets shell timeout
Useful in root's .profile - will auto-logout after TMOUT seconds of inactivity. Close after `seconds` inactive. export TMOUT=seconds (unefunge)

Inverted cowsay
It's quite fun to invert text using "flip.pl" (ref: http://ubuntuforums.org/showthread.php?t=2078323 ). Slightly more challenging is to flip a whole "cowsay". :-)

Assign function keys to your frequent commands
This is a common use of bind. Hitting any key after will output the key's character sequence. This makes possible using it into a bind command. So pressing ctrl+v and then F2 will output "^[[12~", once binded every time you'll press the function key F2 it will execute your command. Added the \n to make it execute it as well.

whowatch: Linux and UNIX interactive, process and users monitoring tool
whowatch is a interactive, ncurses-based, process and users monitoring tool, which updates information in real time. This is a perfect tool for local and remote servers. It displays information about the users currently logged on to the machine, in real-time. Besides standard information (login name, tty, host, user's process), the type of the connection (ie. telnet or ssh) is shown. Display of users command line can be switch to tty idle time. Certain user can be selected and his processes tree may be viewed as well as tree of all system processes. Tree may be displayed with additional column that shows owner of each process. In the process tree mode SIGINT and SIGKILL signals can be sent to the selected process. Killing processes is just as simple and fun as deleting lines on the screen.

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.

Sort the size usage of a directory tree by gigabytes, kilobytes, megabytes, then bytes.
Probably only works with GNU du and modern perls.

Find removed files still in use via /proc
Oracle DBA remove some logfiles which are still open by the database and he is complaining the space has not been reclaimed? Use the above command to find out what PID needs to be stopped. Or alternatively recover the file via: $ cp /proc/pid/fd/filehandle /new/file.txt

Nmap list IPs in a network and saves in a txt

Get your outgoing IP address
Instead of opening your browser, googling "whatismyip"... Also useful for scripts. dig can be found in the dnsutils package.


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