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Record audio and video from webcam using mencoder

Record audio to MP3 stream and video to MPEG-4 stream from webcam to AVI file using mencoder. Gives floating point exception in some mencoder versions.
This is sample output - yours may be different.
6

mencoder tv:// -tv driver=v4l2:width=800:height=600:device=/dev/video0:fps=30:outfmt=yuy2:forceaudio:alsa:adevice=hw.2,0 -ovc lavc -lavcopts vcodec=mpeg4:vbitrate=1800 -ffourcc xvid -oac mp3lame -lameopts cbr=128 -o output.avi

ivalladt · 2009-09-15 19:46:06 5
View webcam output using mplayer

View webcam output using mplayer, with correct fps and outfmt settings according to my webcam model.
This is sample output - yours may be different.
5

mplayer tv:// -tv driver=v4l2:width=640:height=480:device=/dev/video0:fps=30:outfmt=yuy2

ivalladt · 2009-09-15 19:41:41 5
Execute all SQL files in a directory
This is sample output - yours may be different.
0

cat *.sql | mysql <db_name>

rehanift · 2009-09-15 17:28:35 3
Record audio and video from webcam using ffmpeg

Record from a webcam, audio using ALSA encoded as MP3, video as MPEG-4.
This is sample output - yours may be different.
5

ffmpeg -f alsa -r 16000 -i hw:2,0 -f video4linux2 -s 800x600 -i /dev/video0 -r 30 -f avi -vcodec mpeg4 -vtag xvid -sameq -acodec libmp3lame -ab 96k output.avi

ivalladt · 2009-09-15 17:03:25 5
convert a,b,c to ('a','b','c') for use in SQL in-clauses
This is sample output - yours may be different.
1

echo a,b,c | sed -e s/,/\',\'/g -e s/^/$\'/ -e s/$/\'$/

sharfah · 2009-09-15 15:52:01 5
Remove all files but one starting with a letter(s)

Remove everything in current directory except files starting with "ca".
This is sample output - yours may be different.
1

rm -rf [a-bd-zA-Z0-9]* c[b-zA-Z0-9]*

arcege · 2009-09-15 14:22:56 7
Extract audio track from a video file using mencoder

Extracts an MP3 encoded audio stream from an input video file.
This is sample output - yours may be different.
3

mencoder -of rawaudio -ovc copy -oac mp3lame -o output.mp3 input.avi

ivalladt · 2009-09-15 11:28:01 3
Substitute audio track of video file using mencoder

Creates a new video file with video stream copied from input file and a different audio stream
This is sample output - yours may be different.
2

mencoder -ovc copy -audiofile input.mp3 -oac copy input.avi -o output.avi

ivalladt · 2009-09-15 11:26:05 3
Remove sound from video file using mencoder

Remove sound from input video file, output video stream is copied from input video stream, with no audio.
This is sample output - yours may be different.
1

mencoder -ovc copy -nosound input.avi -o output.avi

ivalladt · 2009-09-15 11:22:51 6
Fix UTF-8 text files misinterpreted as ISO 8859-1 due to Byte Order Mark (BOM) of the Unicode Standard.

Fixes the faulty files with perl, which may exist on more platforms
This is sample output - yours may be different.
0

perl -i -pe 's/\xef\xbb\xbf//g' <file>

pfredrik · 2009-09-15 11:22:43 4

This command creates tar zip of a directory and its sub-directories. Show Sample Output

tar cvfz dir_name.tgz dir/

unixmonkey6220 · 2009-09-15 10:20:20 4

Happy Days

AFAIR this is the wording ;)
This is sample output - yours may be different.
5

echo {'1,2,3',4}" o'clock" ROCK

danam · 2009-09-15 10:12:49 11
Incase you miss the famous 'C:\>' prompt
This is sample output - yours may be different.
1

export PS1='C:${PWD//\//\\\}>'

jldbasa · 2009-09-15 10:06:25 4
Find UTF-8 text files misinterpreted as ISO 8859-1 due to Byte Order Mark (BOM) of the Unicode Standard.

Same thing, only "head" instead of grep/egrep.. Show Sample Output
This is sample output - yours may be different.
```
Match: ./wps.ear/wps.war/themes/html/QPG/pageHeader.html
```
0

find -type f |while read a;do [ "`head -c3 -- "${a}"`" == $'\xef\xbb\xbf' ] && echo "Match: ${a}";done

pfredrik · 2009-09-15 08:43:21 3
Backup files older than 1 day on /home/dir, gzip them, moving old file to a dated file.

Useful for backing up old files, custom logs, etc. via a cronjob. Show Sample Output
This is sample output - yours may be different.
```
-rw-rw-r--    1 root     root        46705 Sep 13 14:30 file2.rpm
-rw-rw-r--    1 rms      rms         46705 Sep 13 14:30 file22.rpm

-rw-rw-r--    1 root     root        44227 Sep 13 14:30 file2.rpm_2009-09-15.gz
-rw-rw-r--    1 rms      rms         44228 Sep 13 14:30 file22.rpm_2009-09-15.gz
```
9

find /home/dir -mtime +1 -print -exec gzip -9 {} \; -exec mv {}.gz {}_`date +%F`.gz \;

sagan · 2009-09-15 06:49:59 10
Setting reserved blocks percentage to 1%

According to tune2fs manual, reserved blocks are designed to keep your system from failing when you run out of space. Its reserves space for privileged processes such as daemons (like syslogd, for ex.) and other root level processes; also the reserved space can prevent the filesystem from fragmenting as it fills up. By default this is 5% regardless of the size of the partition. http://www.ducea.com/2008/03/04/ext3-reserved-blocks-percentage/
This is sample output - yours may be different.
2

sudo tune2fs -m 1 /dev/sda4

bassel · 2009-09-14 21:11:55 5
Testing hard disk reading speed
This is sample output - yours may be different.
13

hdparm -t /dev/sda

bassel · 2009-09-14 21:04:08 9
Check variable has been set

Works in all shells. Does not require a test. Handles like an assertion. Show Sample Output
This is sample output - yours may be different.
```
sh: VAR: unset variable
```
-1

: ${VAR:?unset variable}

arcege · 2009-09-14 19:41:01 4
erase content from a cdrw
This is sample output - yours may be different.
1

cdrecord -v -blank=all -force

eastwind · 2009-09-14 19:21:15 7
burn an iso to cd or dvd
This is sample output - yours may be different.
-1

cdrecord -v path_to_iso_image.iso

eastwind · 2009-09-14 19:20:12 4
random xkcd comic

i sorta stole this from http://www.shell-fu.org/lister.php?id=878#MTC_form but it didn't work, so here it is, fixed. --- updated to work with jpegs, and to use a fancy positive look behind assertion.
This is sample output - yours may be different.
6

display "$(wget -q http://dynamic.xkcd.com/comic/random/ -O - | grep -Po '(?<=")http://imgs.xkcd.com/comics/[^"]+(png|jpg)')"

grokskookum · 2009-09-14 18:40:14 5
Check variable has been set
This is sample output - yours may be different.
1

[ -z "$VAR" ] && echo "VAR has not been set" && exit 1

sharfah · 2009-09-14 17:03:16 4
Happy Days

This never gets old Show Sample Output
This is sample output - yours may be different.
```
you'll just have to see now wont you
```
4

echo {1..3}" o'clock" ROCK

JackiesJungle · 2009-09-14 15:39:07 5
view file content with echo

another replacement for cat.
This is sample output - yours may be different.
-2

echo "$(</etc/issue)"

mobidyc · 2009-09-14 09:44:35 34
search for a file in PATH

Also searches for aliases and shell builtins Show Sample Output
This is sample output - yours may be different.
```
root@fs3:~# type nvgui
nvgui is /usr/bin/nvgui
root@serv:~# type rm
rm is /bin/rm
root@fs3:~# type alias
alias is a shell builtin
root@serv:~# 
```
4

type <filename>

danam · 2009-09-14 09:37:23 5
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Get simple weather info from a zip code

$ weather 97405

List the libraries used by an application

For example, you need to make a copy of all the libraries that a certain application uses, with this command you can list and copy them.

cpu and memory usage top 10 under Linux

The original version gives an error, here is the correct output

Alias for lazy tmux create/reattach

Indent all the files in a project using emacs

use -iname \*[.ch] instead of -iname \*.c -o -iname \*.h

Clone or rescue a block device

If you use the logfile feature of ddrescue, the data is rescued very efficiently (only the needed blocks are read). Also you can interrupt the rescue at any time and resume it later at the same point. http://www.gnu.org/software/ddrescue/ddrescue.html

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"

Mute xterm

Disable the annoying beep in xterm

convert UNIX timestamp to UTC timestamp

date -ud @1320198157

Get AWS temporary credentials ready to export based on a MFA virtual appliance

You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

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