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Commands by mohan43u from sorted by
Terminal - Commands by mohan43u - 13 results
ffmpeg -f alsa -itsoffset 00:00:02.000 -ac 2 -i hw:0,0 -f x11grab -s $(xwininfo -root | grep 'geometry' | awk '{print $2;}') -r 10 -i :0.0 -sameq -f mp4 -s wvga -y intro.mp4
2010-03-31 09:33:05
User: mohan43u
Functions: awk grep
4

Yet another x11grab using ffmpeg. I also added mic input to the capturing video stream using alsa. Yet I need to find out how to capture audio which is currently playing.

lsmod | cut -d' ' -f1 | xargs modinfo | egrep '^file|^desc|^dep' | sed -e'/^dep/s/$/\n/g'
2009-11-17 02:13:34
User: mohan43u
2

Run this as root, it will be helpful to quickly get information about the loaded kernel modules.

dpkg -S `which nm` | cut -d':' -f1 | (read PACKAGE; echo "[${PACKAGE}]"; dpkg -s "${PACKAGE}"; dpkg -L "${PACKAGE}") | less
2009-07-14 20:21:48
User: mohan43u
Functions: cut echo read
Tags: which dpkg
2

In Debian based distros, this command will list 'binutils' package details which contains 'nm' command. You can replace 'nm' to any other command.

echo "${STRING}" | tr '[A-Z]' '[a-z]' | awk '{print toupper(substr($0,1,1))substr($0,2);}'
2009-06-23 21:11:34
User: mohan43u
Functions: awk echo tr
Tags: awk tr
0

Helpful when we want to do mass file renaming(especially mp3s).

find . -depth -type d -exec du -s {} \; | sort -k1nr
2009-06-23 20:52:35
User: mohan43u
Functions: du find sort
Tags: sort find du
4

somewhat faster version to see the size of our directories. Size will be in Kilo Bytes. to view smallest first change '-k1nr' to '-k1n'.

(Command too long..See sample Output..)
2009-06-14 20:34:37
User: mohan43u
Tags: bash sed echo tr od
-3

curl doesn't provide url-encoding for 'GET' data, it have an option '--data-urlencode', but its only for 'POST' data. Thats why I need to write down this commandline. With 'perl', 'php' and 'python', this is one liner, but just I wrote it for fun. Works in Ubuntu, will work in all linux varients(I hope it will work in unix varients also).

find `echo "${PATH}" | tr ':' ' '` -type f | while read COMMAND; do man -f "${COMMAND##*/}"; done
2009-06-13 19:56:24
User: mohan43u
Functions: find man read tr
Tags: man find read while tr
3

Obviously, you can replace 'man' command with any command in this command line to do useful things. I just want to mention that there is a way to list all the commands which you can execute directly without giving fullpath.

Normally all important commands will be placed in your PATH directories. This commandline uses that variable to get commands. Works in Ubuntu, will work in all 'manpage' configured *nix systems.

find /var/log -type f -exec file {} \; | grep 'text' | cut -d' ' -f1 | sed -e's/:$//g' | grep -v '[0-9]$' | xargs tail -f
2009-06-03 09:47:08
User: mohan43u
Functions: cut file find grep sed tail xargs
Tags: tail
6

Works in Ubuntu, I hope it will work on all Linux machines. For Unixes, tail should be capable of handling more than one file with '-f' option.

This command line simply take log files which are text files, and not ending with a number, and it will continuously monitor those files.

Putting one alias in .profile will be more useful.

sed -e's/%\([0-9A-F][0-9A-F]\)/\\\\\x\1/g' | xargs echo -e
2009-05-25 05:37:44
User: mohan43u
Functions: echo sed xargs
10
echo "http%3A%2F%2Fwww.google.com" | sed -e's/%\([0-9A-F][0-9A-F]\)/\\\\\x\1/g' | xargs echo -e

http://www.google.com

Works under bash on linux. just alter the '-e' option to its corresponding equivalence in your system to execute escape characters correctly.

cpp /usr/include/stdio.h | grep -v '^#' | grep -v '^$' | less
2009-05-22 22:40:25
User: mohan43u
Functions: cpp grep
4

will display typedefs, structs, unions and functions declared in 'stdio.h'(checkout _IO_FILE structure). It will be helpful if we want to know what a particular header file will offer to us. Command 'cpp' is GNU's C Preprocessor.

ffmpeg -i <filename>.flv -vn <filename>.mp3
$ mplayer -dumpaudio -dumpfile <filename>.mp3 <filename>.flv
find -depth . | (while read FULLPATH; do BASENAME=`basename "${FULLPATH}"`; DIRNAME=`dirname "${FULLPATH}"`; mv "${DIRNAME}/${BASENAME}" "${DIRNAME}/${BASENAME// /_}"; done)
2009-03-24 21:04:32
User: mohan43u
Functions: find mv read
-9

Takes filenames and directory names and replace space to '_'.