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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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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"

Hide or show Desktop Icons on MacOS

Hides all Files and Folders on the MacOS Desktop. To show files and folders, type "true" instead of "false". "Finder" at the end is case sensitive, "finder" doesn’t work

List the Sizes of Folders and Directories

copy working directory and compress it on-the-fly while showing progress

What happens here is we tell tar to create "-c" an archive of all files in current dir "." (recursively) and output the data to stdout "-f -". Next we specify the size "-s" to pv of all files in current dir. The "du -sb . | awk ?{print $1}?" returns number of bytes in current dir, and it gets fed as "-s" parameter to pv. Next we gzip the whole content and output the result to out.tgz file. This way "pv" knows how much data is still left to be processed and shows us that it will take yet another 4 mins 49 secs to finish. Credit: Peteris Krumins http://www.catonmat.net/blog/unix-utilities-pipe-viewer/

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

Detect encoding of a text file

This command gives you the charset of a text file, which would be handy if you have no idea of the encoding.

cpu info

Renaming a file without overwiting an existing file name

Sometimes in a hurry you may move or copy a file using an already existent file name. If you aliased the cp and mv command with the -i option you are prompted for a confirmation before overwriting but if your aliases aren't there you will loose the target file! The -b option will force the mv command to check if the destination file already exists and if it is already there a backup copy with an ending ~ is created.

cd to (or operate on) a file across parallel directories

This is useful for quickly jumping around branches in a file system, or operating on a parellel file. This is tested in bash. cd to (substitute in PWD, a for b) where PWD is the bash environmental variable for the "working directory"

ROT13 using the tr command

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All commands (14,187)

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