Commands by h3xx (20)

  • Real gurus don't need fancy tools like iftop or jnettop. Show Sample Output


    9
    tcpdump -w - |pv -bert >/dev/null
    h3xx · 2011-12-14 00:24:02 4
  • For when you need a quick spell check. Show Sample Output


    10
    aspell -a <<< '<WORDS>'
    h3xx · 2011-11-30 01:47:46 3
  • This causes cp to detect and omit large blocks of nulls. Sparse files are useful for implying a lot of disk space without actually having to write it all out. http://en.wikipedia.org/wiki/Sparse_file You can use it in a pipe too: dd if=/dev/zero bs=1M count=5 |cp --sparse=always /dev/stdin SPARSE_FILE Show Sample Output


    4
    cp --sparse=always <SRC> <DST>
    h3xx · 2011-09-07 08:02:50 0
  • This is shorter and actually much faster than >/dev/null (see sample output for timings) Plus, it looks like a disappointed face emoticon. Show Sample Output


    22
    <COMMAND> |:
    h3xx · 2011-08-28 23:48:29 13
  • Ever ask yourself "How much data would be lost if I pressed the reset button?" Scary, isn't it? Show Sample Output


    34
    grep ^Dirty /proc/meminfo
    h3xx · 2011-08-24 08:48:49 8
  • Tells you everything you could ever want to know about all files and subdirectories. Great for package creators. Totally secure too. On my Slackware box, this gets set upon login: LS_OPTIONS='-F -b -T 0 --color=auto' and alias ls='/bin/ls $LS_OPTIONS' which works great. Show Sample Output


    2
    lsr() { find "${@:-.}" -print0 |sort -z |xargs -0 ls $LS_OPTIONS -dla; }
    h3xx · 2011-08-15 03:10:58 0

  • 0
    echo $(($(ulimit -u)-$(pgrep -u $USER|wc -l))
    h3xx · 2011-07-30 05:03:36 0
  • These are way better than fortune(6). Show Sample Output


    2
    grep -2riP '\b(fuck|shit|bitch|tits|ass\b)' /usr/src/linux/
    h3xx · 2011-07-27 23:11:02 1
  • For instance: find . -type f -name '*.wav' -print0 |xargs -0 -P 3 -n 1 flac -V8 will encode all .wav files into FLAC in parallel. Explanation of xargs flags: -P [max-procs]: Max number of invocations to run at once. Set to 0 to run all at once [potentially dangerous re: excessive RAM usage]. -n [max-args]: Max number of arguments from the list to send to each invocation. -0: Stdin is a null-terminated list. I use xargs to build parallel-processing frameworks into my scripts like the one here: http://pastebin.com/1GvcifYa


    2
    xargs -P 3 -n 1 <COMMAND> < <FILE_LIST>
    h3xx · 2011-07-25 22:53:32 0
  • Crash Override, man! Apparently the exec call tricks BASH into setting the output buffer size to 0 under the assumption that the system (or the calling shell) will handle the output buffering. trapping the ERR signal will stop the subshell from dying and sending the ERR signal to the main script--which will terminate immediately if it does--when the program fails. The only problem is that the kernel will output a whole bunch of stack trace garbage directly to the console device once the process segfaults, so there's no way to prevent it from being output [that I know of].


    0
    (trap 'true' ERR; exec <SEGFAULT_PRONE_PROGRAM>)
    h3xx · 2011-07-25 02:30:52 0
  • Even adds a newline.


    1
    xxd -p <<< <STRING>
    h3xx · 2011-07-24 19:16:32 0

  • 0
    read VAR1 VAR2 VAR3 <<< aa bb cc; echo $VAR2
    h3xx · 2011-07-24 18:56:30 0
  • You can also save EXIF information by copying it to temp.jpg: jpegtran -optimize -outfile temp.jpg <JPEG> && jhead -te temp.jpg "$_" && mv temp.jpg "$_"


    0
    jpegtran -optimize -outfile temp.jpg <JPEG> && mv temp.jpg "$_"
    h3xx · 2011-07-24 08:55:46 0
  • Or, aumix -v -5 Map these to key combinations in your window manager and who needs special buttons?


    0
    aumix -v +5
    h3xx · 2011-07-24 07:41:40 0
  • This forces X back to its maximum resolution configured. To get a list, type `xrandr'.


    2
    xrandr -s 0
    h3xx · 2011-07-24 07:38:01 0
  • Works really well for playing DVDs, which have the volume turned way down for some reason. The `2' method is better IMHO because it will adjust to changing loud/soft parts. If you want to add it to your ~/.mplayer/config: # format: volnorm[=method:target] # method: # 1: use single sample (default) # 2: multiple samples # target: # default is 0.25 af-add=volnorm=2:0.75


    3
    mplayer -af volnorm=2:0.75 dvd://
    h3xx · 2011-07-24 07:26:51 0
  • Make sure the file contents can't be retrieved if anyone gets ahold of your physical hard drive. With hard drive partition: gpg --default-recipient-self -o /path/to/encrypted_backup.gpg -e /dev/sdb1 && shred -z /dev/sdb1 WARNING/disclaimer: Be sure you... F&%k it--just don't try this.


    0
    gpg -e --default-recipient-self <SENSITIVE_FILE> && shred -zu "$_"
    h3xx · 2011-07-24 05:51:47 0
  • Skip forward and back using the < and > keys. Display the file title with I.


    1
    mplayer -playlist <(find "$PWD" -type f)
    h3xx · 2011-07-24 03:27:03 0
  • zless /proc/config.gz


    0
    zgrep CONFIG_MAGIC_SYSRQ /proc/config.gz
    h3xx · 2011-07-24 02:06:09 0
  • This will affect all invocations of grep, even when it is called from inside a script.


    1
    export GREP_OPTIONS='--color=auto'
    h3xx · 2011-07-24 01:32:10 0

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Create a persistent remote Proxy server through an SSH channel
Create a persistent remote Proxy server through an SSH channel.

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Stamp a text line on top of the pdf pages.
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Check your unread Gmail from the command line
Just an alternative with more advanced formating for readability purpose. It now uses colors (too much for me but it's a kind of proof-of-concept), and adjust columns.

Get your outgoing IP address

Determining the excat memory usages by certain PID
this command gives you the total number of memory usuage and open files by the perticuler PID.

Remove multiple same rpm packages
If somehow if you get more than 1 same name rpm package install, then it cannot be removed by using simple rpm -e as it gives you more than one rpm matches error. The --matches will help to remove all the same name rpm packages.

Swap a file or dir with quick resotre
This lets you replace a file or directory and quickly revert if something goes wrong. For example, the current version of a website's files are in public_html. Put a new version of the site in public_html~ and execute the command. The names are swapped. If anything goes wrong, execute it again (up arrow or !!).

Save a file you edited in vim without the needed permissions
probably just like 1204, but uses tee as a filter (+ I actually understand how this one works)

Easy way to scroll up und down to change to one of n last visited directories.
This alias is meant to append n (here is n=10) most recently used cd commands to the bottom of history file. This way you can easily change to one of previous visited directories simply by hitting 1-10 times arrow up key. Hint: You can make more aliases implying the same rule for any set of frequently used long and complex commands like: mkisof, rdesktop, gpg...


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