Commands by Zenexer (2)

  • Thanks to OpenSSL, you can quickly and easily generate MD5 hashes for your passwords. Alternative (thanks to linuxrawkstar and atoponce): echo -n 'text to be encrypted' | md5sum - Note that the above method does not utlise OpenSSL. Show Sample Output


    17
    echo -n 'text to be encrypted' | openssl md5
    Zenexer · 2009-03-18 00:11:46 4
  • A simple but effective replacement for ps aux. I used to waste my time running ps over and over; top is the way to go. It also allows complex sorting options. Press q to exit "nicely" (Ctrl + C is always an option, of course). Note that the list updates each second, resorting in the process; if you're trying to grab a specific PID, you might be better off with ps. htop Alternatively, htop is available, though it may not come pre-installed. htop is slightly more interactive than top and includes color coding, visuals, and a nice interface for selecting and then killing processes. (Thanks to bwoodacre for this great tool.) Show Sample Output


    -5
    top
    Zenexer · 2009-03-18 00:03:42 6

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escape any command aliases
e.g. if rm is aliased for 'rm -i', you can escape the alias by prepending a backslash: rm [file] # WILL prompt for confirmation per the alias \rm [file] # will NOT prompt for confirmation per the default behavior of the command

Remove all the files except abc in the directory
Finds all files in the current directory and deletes them besides file called "abc"

Download all images from a 4chan thread
Useful for ripping wallpaper from 4chan.org/wg

Get curenttly playing track in Last.fm radio

List all TCP opened ports on localhost in LISTEN mode
Alternative of OJM snippet : This one show the IP too, where ports bind. It's very important, because if there's only 127.0.0.1 instead of 0.0.0.0, connections from internet are rejected.

create an emergency swapfile when the existing swap space is getting tight
Create a temporary file that acts as swap space. In this example it's a 1GB file at the root of the file system. This additional capacity is added to the existing swap space.

delete duplicate lines from a file and keep the order of the other lines
i wanted to delete all duplicate lines from .bash_history and keep the order of the other lines. the command cat's the file and adds line numbers, then sorts by the second column. afterwards uniq omits repeated lines, but skips the first field (the line number). then it sorts by the line numbers and at the end cuts the numbers off.

view the system memory in clear text
see what's in your memory right now... sometimes you find passwords, account numbers and url's that were recently used. Anyone have a safe command to clear the memory without rebooting?

Who has the most Apache connections.
This will tell you who has the most Apache connections by IP (replace IPHERE with the actual IP you wish to check). Or if you wish, remove | grep -c IPHERE for the full list.

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"


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