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Commands by h3xx

Commands by h3xx from sorted by
Terminal - Commands by h3xx - 20 results
tcpdump -w - |pv -bert >/dev/null
2011-12-14 00:24:02
User: h3xx
Functions: tcpdump
Tags: tcpdump pv network performance networking
6
Up
Down
Show network throughput

Real gurus don't need fancy tools like iftop or jnettop.

Show sample output | Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
aspell -a <<< '<WORDS>'
2011-11-30 01:47:46
User: h3xx
Tags: aspell spellcheck English
10
Up
Down
Check your spelling

For when you need a quick spell check.

Show sample output | Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cp --sparse=always <SRC> <DST>
2011-09-07 08:02:50
User: h3xx
Functions: cp
Tags: cp sparse files sparse
4
Up
Down
Copy sparse files

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
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<COMMAND> |:
2011-08-28 23:48:29
User: h3xx
Tags: pipe redirecting output built-in data sink
25
Up
Down
Fast, built-in pipe-based data sink

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 | Comments (12) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
grep ^Dirty /proc/meminfo
2011-08-24 08:48:49
User: h3xx
Functions: grep
Tags: Filesystem grep proc buffer
28
Up
Down
Find out how much data is waiting to be written to disk

Ever ask yourself "How much data would be lost if I pressed the reset button?"

Scary, isn't it?

Show sample output | Comments (7) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
lsr() { find "${@:-.}" -print0 |sort -z |xargs -0 ls $LS_OPTIONS -dla; }
2011-08-15 03:10:58
User: h3xx
Functions: find ls sort xargs
Tags: sort find ls xargs function list
2
Up
Down
Sorted, recursive long file listing

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 | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo $(($(ulimit -u)-$(pgrep -u $USER|wc -l))
2011-07-30 05:03:36
User: h3xx
Functions: echo ulimit wc
Tags: bash kill wc proc process ulimit users processes limits.conf
0
Up
Down
See how many more processes are allowed, awesome!
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
grep -2riP '\b(fuck|shit|bitch|tits|ass\b)' /usr/src/linux/
2011-07-27 23:11:02
User: h3xx
Functions: grep
Tags: kernel funny easter-egg
1
Up
Down
Read funny developer comments in the Linux source tree

These are way better than fortune(6).

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
xargs -P 3 -n 1 <COMMAND> < <FILE_LIST>
2011-07-25 22:53:32
User: h3xx
Functions: xargs
Tags: multicore xargs parallel
0
Up
Down
Multi-thread any command

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

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(trap 'true' ERR; exec <SEGFAULT_PRONE_PROGRAM>)
2011-07-25 02:30:52
User: h3xx
Functions: exec trap
Tags: trap script error
0
Up
Down
Collect output from a segfaulting program and keep the script from dying

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].

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xxd -p <<< <STRING>
2011-07-24 19:16:32
User: h3xx
Tags: hex ascii convert
1
Up
Down
convert ascii string to hex

Even adds a newline.

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read VAR1 VAR2 VAR3 <<< aa bb cc; echo $VAR2
2011-07-24 18:56:30
User: h3xx
Functions: echo read
0
Up
Down
split a string (2)
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jpegtran -optimize -outfile temp.jpg <JPEG> && mv temp.jpg "$_"
2011-07-24 08:55:46
User: h3xx
Functions: mv
Tags: jpeg
0
Up
Down
Losslessly optimize JPEG files for file size

You can also save EXIF information by copying it to temp.jpg:

jpegtran -optimize -outfile temp.jpg <JPEG> && jhead -te temp.jpg "$_" && mv temp.jpg "$_"
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aumix -v +5
2011-07-24 07:41:40
User: h3xx
Functions: aumix
Tags: alsa
0
Up
Down
Ramp the system volume up 5%

Or,

aumix -v -5

Map these to key combinations in your window manager and who needs special buttons?

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xrandr -s 0
2011-07-24 07:38:01
User: h3xx
Tags: X resolution xrandr
2
Up
Down
Recover resolution when a fullscreen program crashes and you're stuck with a tiny X resolution

This forces X back to its maximum resolution configured. To get a list, type `xrandr'.

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mplayer -af volnorm=2:0.75 dvd://
2011-07-24 07:26:51
User: h3xx
Tags: mplayer volume
1
Up
Down
Normalize volume output in MPlayer

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

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gpg -e --default-recipient-self <SENSITIVE_FILE> && shred -zu "$_"
2011-07-24 05:51:47
User: h3xx
Functions: gpg shred
Tags: GPG shred
0
Up
Down
Destroy file contents after encryption

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.

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mplayer -playlist <(find "$PWD" -type f)
2011-07-24 03:27:03
User: h3xx
Functions: find
Tags: mplayer fd
0
Up
Down
Play all files in the directory using MPlayer

Skip forward and back using the < and > keys. Display the file title with I.

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zgrep CONFIG_MAGIC_SYSRQ /proc/config.gz
2011-07-24 02:06:09
User: h3xx
Functions: zgrep
Tags: kernel proc
0
Up
Down
Figure out if your kernel has an option enabled
zless /proc/config.gz
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export GREP_OPTIONS='--color=auto'
2011-07-24 01:32:10
User: h3xx
Functions: export
Tags: color grep
1
Up
Down
Enable color pattern match highlighting in grep(1)

This will affect all invocations of grep, even when it is called from inside a script.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate