Commands by Zenexer (2)

  • Quickly generate an MD5 hash for a text string using OpenSSL

    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


    19
    echo -n 'text to be encrypted' | openssl md5
    Zenexer · 2009-03-18 00:11:46 4
  • View process statistics in realtime

    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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AWK: Set Field Separator from command line

cycle through everything sox knows how to read, playing only the first three seconds
I wasted two hours reading the sox documentation and searching on the web for the format of some obscure fscking sound sample, and then finally came up with this. This plays only the first three seconds of your unknown formatted sound file using every one of sox's built-in filetypes. If you don't get an exact match, you may get close. . I could not fit every single type in and keep it under 127 characters, so you will have to replace "..." with the full list obtainable by `$ sox --help` (or try `Show sample output`) . note: /usr/bin/play should be linked to sox on most systems.

Using mplayer to play the audio only but suppress the video

Print the last modified file

Easy Persistent SSH Connections Using Screen
Use as: $ s host1 Will ssh to remote host upon first invocation. Then use C-a d to detatch. Running "s host1" again will resume the shell session on the remote host. Only useful in LAN environment. You'd want to start the screen on the remote host over a WAN. Adapted from Hack 34 in Linux Server Hacks 2nd Addition.

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"

Find processes stuck in dreaded "D" state aka IO Wait
Lots of fun to run on nfs clients when the server or network connection is having issues

remove hostname from known_hosts

Text message on wallpaper
Display some text on the wallpaper especially warning messages

Randomly run command
Randomly decide whether to run a command, or fail. It's useful for testing purposes. . Usage: ran PERCENTAGE COMMAND [ARGS] Note: In this version the percentage is required. . This is like @sesom42 and @snipertyler's commands but in a USABLE form. . e.g. In your complicated shell script, put "ran 99" before a crucial component. Now, it will fail 1% of the time allowing you to test the failure code-path. $ ran 99 my_complex_program arg1 arg2

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