Commands by unixmonkey365 (6)

  • 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. Show Sample Output


    1
    for x in 8svx aif aifc aiff aiffc ... wv wve xa xi ; do echo $x ; play -q -t $x soundfile trim 0 3 ; done
    unixmonkey365 · 2011-12-09 00:23:45 7
  • This is just a phrase I use to help me remember which way is what when using nice (top, renice, etc.), and not a command, (unless you really want this in your .bash_history to help remind you.) I was using the command `man nice ` way too much just to look up which way is what. This saves 9 keystrokes every time I remember it. Make sure you downvote me if you think mnemonics sux. Otherwise I hope this helps someone else.


    1
    # Negative is Not Nice
    unixmonkey365 · 2011-11-29 19:05:23 6
  • Someone over at Mozilla dot Org probably said, "I know, let's create a super-duper universal replacement for browser cookies that are persistent and even more creepy and then NOT give our browser users the tools they need to monitor, read, block or selectively remove them!" . This will let you see all the DOM object users in all your firefox profiles. Feel free to toss a `| sort -u` on the end to remove dupes. . I highly recommend you treat these as "session cookies" by scripting something that deletes this sqlite database during each firefox start-up. . note: does not do anything for so-called "flash cookies" Show Sample Output


    8
    strings ~/.mozilla/firefox/*/webappsstore.sqlite|grep -Eo "^.+\.:" |rev
    unixmonkey365 · 2011-09-26 15:23:09 10
  • Another function to stick into your .bashrc This spits out the time two minutes in the future, but already formatted for pasting into your crontab file for testing without any thought required on your part. Frequently things don't work the way you expect inside a crontab job, and you probably want to find out now that your $PATH is completely different inside of cron or other global variables aren't defined. So this will generate a date you can use for testing now, and then later you can change it to run at 5:37 am on a Sunday evening. Show Sample Output


    7
    crontest () { date '-d +2 minutes' +'%M %k %d %m *'; }
    unixmonkey365 · 2011-09-16 00:47:24 5
  • cn stands for "Cat Null" . The idea is that sometimes you run across something on maybe a webpage - like commandlinefu - that you want to try out on your terminal. You could put a '#' in and then paste it, but what if it is several lines? . This command will echo the pasted characters to the screen and divert them to the bit bucket. . Put this simple alias in your .bashrc, hit cn, paste away, and hit a ctrl+c or a ctrl+d when you are done to get your prompt back. Show Sample Output


    -3
    alias cn='cat > /dev/null'
    unixmonkey365 · 2011-09-16 00:00:28 7
  • Evoke from the command like as: timeDNS commandlinefu.com . This isn't too terribly practical, but it is a good code example of using subshells to run the queries in parallel and the use of an "anonymous function" (a/k/a "inline group") to group i/o. . I'm assuming you have already defined your local DNS cache as ${local_DNS}, (here, it's 192.168.0.1). . You do need to install `moreutils` to get `sponge`. . If you're willing to wait, a slower version w/o sponge, (and w/o sorting), is this: . DNS () { for x in "192.168.0.1" "208.67.222.222" "208.67.220.220" "198.153.192.1" "198.153.194.1" "156.154.70.1" "156.154.71.1" "8.8.8.8" "8.8.4.4"; do (echo -n "$x "; dig @"$x" "$*"|grep Query) ; done ; } Show Sample Output


    1
    timeDNS () { { for x in "${local_DNS}" "208.67.222.222" "208.67.220.220" "198.153.192.1" "198.153.194.1" "156.154.70.1" "156.154.71.1" "8.8.8.8" "8.8.4.4"; do ({ echo -n "$x "; dig @"$x" "$*"|grep Query ; }|sponge &) done ; } | sort -n -k5 ; }
    unixmonkey365 · 2011-08-18 01:11:53 6

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Limit the transfer rate and size of data over a pipe
This example will close the pipe after transferring 100MB at a speed of 3MB per second.

no # comments, blank lines, white space. # can start in any column
The shortest and most complete comment/blank line remover... Any line where the first non-whitespace character is # (ie, indented # comments), and all null and blank lines are removed. Use the alias as a filter: $ noc /etc/hosts or $ grep server /etc/hosts | noc Change to nawk depending awk versions.

Monitor incoming connections of proxies and balancers.
Maybe this will help you to monitor your load balancers or reverse proxies if you happen to use them. This is useful to discover TIME OUTS and this will let you know if one or more of your application servers is not connected by checking.

Convert embedded spaces in filenames to "_" (underscore)
This command converts filenames with embedded spaces in the current directory replacing spaces with the underscore ("_") character.

Fetch the current human population of Earth
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Create a continuous digital clock in Linux terminal
Same effect, only shell commands.

Extract dd-image from VirtualBox VDI container and mount it
Tested with NTFS and found on this site: http://forensicir.blogspot.com/2008/01/virtualbox-and-forensics-tools.html The first 32256 bytes is the MBR

Binary search/replace
Replace all instances of "A" with "B" in file "source" saved as file "destination". !! IF A/B is multi-byte, then separate bytes with spaces like so: "s/20\ 0A/00/g".

Run the built in PHP-server in current folder
You must have PHP 5.4.0 or later to be able to run the built in server. This web server is designed for developmental purposes only, and should not be used in production. URI requests are served from the current working directory where PHP was started, unless the -t option is used to specify an explicit document root. If a URI request does not specify a file, then either index.php or index.html in the given directory are returned. If neither file exists, then a 404 response code is returned. If a PHP file is given on the command line when the web server is started it is treated as a "router" script. The script is run at the start of each HTTP request. If this script returns FALSE, then the requested resource is returned as-is. Otherwise the script's output is returned to the browser. Standard MIME types are returned for files with extensions: .css, .gif, .htm, .html, .jpe, .jpeg, .jpg, .js, .png, .svg, and .txt. The .htm and .svg extensions are recognized from PHP 5.4.4 onwards. More information here: http://php.net/manual/en/features.commandline.webserver.php

Get all mac address
I prefer the ip command to ifconfig as ifconfig is supposedly going to be deprecated. Certain IP address aliases can only be seen with the ip command (such as the ones applied by RHCS).


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