Commands using perl (369)

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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"

convert a mp4 video file to mp3 audio file (multiple files)

Get list of servers with a specific port open
Change the -p argument for the port number. See "man nmap" for different ways to specify address ranges.

MSDOS command to check existance of command and exit batch if failed
This is a command to be used inside of MS-DOS batch files to check existence of commands as preconditions before actual batch processing can be started. If the command is found, batch script continues execution. If not, a message is printed on screen, script then waits for user pressing a key and exits. An error message of the command itself is suppressed for clarity purpose.

Analyse writing style of writing style of a document
Style analyses the surface characteristics of the writing style of a document. It prints various readability grades, length of words, sentences and paragraphs. It can further locate sentences with certain characteristics. If no files are given, the document is read from standard input. style is part of "diction" package

RDP through SSH tunnel
This command will: 1. open an SSH tunnel to 2. go to background 3. wait for 10 seconds for the connection 4. during the 10 seconds wait it will localy run 'rdesktop' to connect to the remote host through the created SSH tunnel. Password-less log in can be achieved (when server allows it) by adding '-p ' to the 'rdesktop' command

Create executable, automountable filesystem in a file, with password!
This is just a proof of concept: A FILE WHICH CAN AUTOMOUNT ITSELF through a SIMPLY ENCODED script. It takes advantage of the OFFSET option of mount, and uses it as a password (see that 9191? just change it to something similar, around 9k). It works fine, mounts, gets modified, updated, and can be moved by just copying it. USAGE: SEE SAMPLE OUTPUT The file is composed of three parts: a) The legible script (about 242 bytes) b) A random text fill to reach the OFFSET size (equals PASSWORD minus 242) c) The actual filesystem Logically, (a)+(b) = PASSWORD, that means OFFSET, and mount uses that option. PLEASE NOTE: THIS IS NOT AN ENCRYPTED FILESYSTEM. To improve it, it can be mounted with a better encryption script and used with encfs or cryptfs. The idea was just to test the concept... with one line :) It applies the original idea of http://www.commandlinefu.com/commands/view/7382/command-for-john-cons for encrypting the file. The embedded bash script can be grown, of course, and the offset recalculation goes fine. I have my own version with bash --init-file to startup a bashrc with a well-defined environment, aliases, variables.

du and sort to find the biggest directories in defined filesystem
This command give a human readable result without messing up the sorting.

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" }

Create AUTH PLAIN string to test SMTP AUTH session
I use this as an alias: alias authplain "printf '\!:1\0\!:1\0\!:2' | mmencode | tr -d '\n' | sed 's/^/AUTH PLAIN /'" then.. # authplain someuser@somedomain.com secretpassword AUTH PLAIN c29tZXVzZXJAc29tZWRvbWFpbi5jb20Ac29tZXVzZXJAc29tZWRvbWFpbi5jb20Ac2VjcmV0cGFzc3dvcmQ= #


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