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sets volume via command line

adjusts the 'Master' channel's volume up by 1dB. Can use command 'amixer' to see other channels : Simple mixer control 'Master',0 or Simple mixer control 'Capture',0 Show Sample Output
This is sample output - yours may be different.
```
Simple mixer control 'Master',0
  Capabilities: pvolume pvolume-joined pswitch pswitch-joined
  Playback channels: Mono
  Limits: Playback 0 - 255
  Mono: Playback 55 [22%] [-50.00dB] [on]
```
0

amixer -c 0 set Master 1dB+

chrisp6825 · 2013-07-25 15:28:45 10
Use Ruby version permanently

Ruby Version Manager (RVM) - https://rvm.io/ Show Sample Output
This is sample output - yours may be different.
```
Using /Users/weng/.rvm/gems/ruby-1.9.3-p448
```
0

rvm --default use ruby-1.9.3

99RedBalloons · 2013-10-04 02:43:59 199
thunderbird commandline invocation to attach email

Opens a window with $1 attached and ready to send.
This is sample output - yours may be different.
0

thunderbird -compose "attachment='file://`pwd`/$*'"

tobi · 2014-01-08 12:22:50 11
Convert serialized PHP data into JSON

Pipe serialized data into the command.
This is sample output - yours may be different.
0

php -r 'echo json_encode( unserialize( file_get_contents( "php://stdin" ) ) );'

westonruter · 2014-07-14 17:09:21 8
To debug asterisk start process
This is sample output - yours may be different.
0

bash -x /etc/init.d/asterisk start

nomikos · 2014-11-05 23:18:45 7
Linux: find names non non-virtual network interfaces

This is used to find externally accessible network interfaces; interfaces that others can connect to us with. By then finding the IP address of these interfaces, we can find addresses that other hosts would use in order to connect to us. Show Sample Output
This is sample output - yours may be different.
```
localhost core # ls -l /sys/class/net/ | grep /devices/ | grep -v /virtual/ | awk '{print $9}'
ens32
```
0

ls -l /sys/class/net/ | grep /devices/ | grep -v /virtual/ | awk '{print $9}'

marksheahan · 2015-02-26 18:46:07 8
Recursively remove directories less than specified size

Removes directories which are less than 1028KB total. This works for systems where blank directories are 4KB. If a directory contains 1 MB (1024KB) or less, it will remove the directory using a path relative to the directory where the command was initially executed (safer than some other options I found). Adjust the 1028 value for your needs. It would be helpful to test the results before proceeding with the removal. Simply run all but the last two commands to see a list of what will be removed: du | awk '{if($1<1028)print;}' | cut -d $'\t' -f 2- If you're unsure what size a blank folder is, test it like this: mkdir test; du test; rmdir test
This is sample output - yours may be different.
0

du | awk '{if($1<1028)print;}' | cut -d $'\t' -f 2- | tr "\n" "\0" | xargs -0 rm -rf

i814u2 · 2015-06-25 16:00:48 11
Copy your ssh public key to a server from a machine that doesn't have ssh-copy-id

This is what I use. You will need netcat installed on both machines. http://stackoverflow.com/a/39323186/3006854
This is sample output - yours may be different.
0

ssh user@host -c 'nc -l 55555 >> ~/.ssh/authorized_keys' & nc HOSTNAME 55555 < ~/.ssh/id_rsa.pub

keith · 2017-04-19 12:39:51 24
Quickly clean log files (assuming you don't want them anymore)

you don't need to echo, just a plain redirect is enough to empty the file
This is sample output - yours may be different.
0

for file in `find /var/log/ -type f -size +5000k`; do > $file; done

svg · 2009-07-03 17:38:21 8

WPA/WPA2 ESSID and password automation with pyrit

This command will automate the creation of ESSIDs and batch processing in pyrit. Give it a list of WPA/WPA2 access points you're targeting and it'll import those ESSIDs and pre-compute the potential password hashes for you, assuming you've got a list of passwords already imported using: pyrit -i dictionary import_passwords Once the command finishes, point pyrit to your packet capture containing a handshake with the attack_db module. Game over. Show Sample Output

gopyrit () { if [ $# -lt 1 ]; then echo $0 '< list of ESSIDs >'; return -1; fi; for i in "$@"; do pyrit -e $i create_essid && pyrit batch; done; pyrit eval }

meathive · 2010-06-19 01:11:00 7

recursive transform all contents of files to lowercase
This is sample output - yours may be different.
0

perl -e "tr/[A-Z]/[a-z]/;" -pi.save $(find . -type f)

miccaman · 2010-11-25 12:48:39 4
Perl One Liner to Generate a Random IP Address
This is sample output - yours may be different.
0

perl -e 'printf join ".", map int rand 256, 1 .. 4;'

gml · 2011-01-16 02:15:29 6
Create a Christmas tree with perl

Require: perl -MCPAN -e 'install Acme::POE::Tree' From: http://www.catonmat.net/blog/christmas-tree-in-the-shell/
This is sample output - yours may be different.
0

perl -MAcme::POE::Tree -e 'Acme::POE::Tree->new()->run()'

anhpht · 2011-10-13 10:33:31 4
Mount a partitoned disk-image file

Mounts a disk-image of a hdd with partitions
This is sample output - yours may be different.
0

IMG="image.img";PART=1;mount -o loop,ro,offset=$(parted $IMG -s unit b print|awk '$1=='$PART' {sub(/B/,"",$2);print $2}') $IMG /mnt/whatever

AndroTux · 2011-12-31 14:58:18 3

Python unicode `explain`

vs. map(unicodedata.name, u'\u2022') Show Sample Output

import unicodedata; map(unicodedata.name, '\u2022'.decode('ascii'))

evandrix · 2012-09-11 10:01:39 4

Join the lines with comma

A more simple way to join lines with paste command than sed. Show Sample Output
This is sample output - yours may be different.
```
line1,line2
```
0

paste -sd, <<< $'line1\nline2'

kodango · 2012-11-13 01:26:05 4
Get unique basewords from Hashcat pot
This is sample output - yours may be different.
0

cut -f 2 -d ':' oclHashcat.pot | egrep -oi '[a-z]{1,20}' | sort | uniq > base.pot

Creek · 2014-07-14 21:03:22 6
slow down/speed up video file
This is sample output - yours may be different.
0

mencoder -speed 2 -o output.avi -ovc lavc -oac mp3lame input.avi

FreedomBen · 2014-11-05 23:57:34 7
Show first IPv4 address for an interface without CIDR mask

Given a network interface (eth0 in this example), find its ip address, without CIDR netmask. Show Sample Output
This is sample output - yours may be different.
```
localhost core # ip addr show dev eth0 | grep -E '\binet\b' | sed 's|.*inet $[^/]*$/.*|\1|' | head -n 1
192.168.128.197
```
0

ip addr show dev eth0 | grep -E '\binet\b' | sed 's|.*inet $[^/]*$/.*|\1|' | head -n 1

marksheahan · 2015-02-26 19:07:10 8
Send pop-up notifications on Gnome
This is sample output - yours may be different.
0

zenity --info --text="I'am a popup"

fundor333 · 2016-08-12 19:04:59 14
Export only one SVG element by ID.

-z, --without-gui -j, --export-id-only -i, --export-id=ID -l, --export-plain-svg=FILENAME In Inkscape Press Ctrl-Shift-o to open object properties panel to give ID to a selected element
This is sample output - yours may be different.
0

inkscape project.svg -z -j -i icon.svg -l b.svg

atemvm · 2018-05-15 14:16:35 193
set timestamp in exif of a image
This is sample output - yours may be different.
0

exiv2 -M"set Exif.Photo.DateTimeOriginal `date "+%Y:%m:%d %H:%M:%S"`" filename.jpg

gecco · 2009-03-18 10:53:46 5
Equivelant of a Wildcard

This is exactly the same as a wildcard - good for times when wildcards are disabled and when you want have a wildcard of a directory that is not your current ({`ls /path/to/dir`}). Does not work on older versions of Bash though.
This is sample output - yours may be different.
0

`ls`

matthewbauer · 2009-08-17 03:56:05 7
Dump all of perl's config info

This dumps all of your installed perl's config information.
This is sample output - yours may be different.
0

perl -le 'use Config; foreach $i (keys %Config) {print "$i : @Config{$i}"}'

chuckr · 2009-09-22 22:14:21 4
Better "hours of video" summary for each file/dir in the current directory

I know this has been beaten to death but finding video files using mime types and printing the "hours of video" for each directory is (IMHO) easier to parse than just a single total. Output is in minutes. Among the other niceties is that it omits printing of non-video files/folders PS: Barely managed to fit it within the 255 character limit :D Show Sample Output
This is sample output - yours may be different.
```
Fundamentals Of Physics - 1724.32
Google Techtalks - 258.292
Introduction to Algorithms - 1805.26
Linear Algebra - 1675.23
```
0

for item in *;do echo -n "$item - ";find "$item" -type f -print0 | xargs -0 file -iNf - | grep video | cut -d: -f1 | xargs -d'\n' /usr/share/doc/mplayer/examples/midentify | grep ID_LENGTH | awk -F= '{sum+=$2} END {print(sum/60)}'; done | grep -v ' - 0$'

jnash · 2009-11-19 06:28:15 3
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Switch to a user with "nologin" shell

You need sudo privileges for this command. Replace username with actual username.

Edit the last or previous command line in an editor then execute

If you would like to edit a previous command, which might be long and complicated, you can use the fc (I think it stands for fix command). Invoke fc alone will edit the last command using the default editor (specified by $FCEDIT, $EDITOR, or emacs, in that order). After you make the changes in the editor, save and exit to execute that command. The fc command is more flexible than what I have described. Please 'man bash' for more information.

Retry the previous command until it exits successfully

Repeat the previously used command (!!) until it exits with a success code (0). To put a delay between attempts you could do something like $ until !!; do sleep 5; done to wait 5 seconds after each attempt.

Convert records in columns to csv

Show all configured ipv4

Short list of all ip. Shows even the newly supported multiple ip address on the same interface (see eth1). For ipv6 use -6

copy last command to clipboard

Copy the last command to clipboard (os x)

Set audible alarm when an IP address comes online

Waiting for your server to finish rebooting? Issue the command above and you will hear a beep when it comes online. The -i 60 flag tells ping to wait for 60 seconds between ping, putting less strain on your system. Vary it to your need. The -a flag tells ping to include an audible bell in the output when a package is received (that is, when your server comes online).

reduce mp3 bitrate (and size, of course)

Useful if you have to put some mp3 files into mobile devices (ie mobile phones with no much memory)

postgresql SQL to show count of ALL tables (relations) including relation-size

Postgresql specific SQL - to show count of ALL tables including relation-size (pg_relation_size = used space on filesystem) - might need a VACUUM ANALYZE before showing all counts correctly !

remove all spaces from all files in current folder

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