Delete single line from multiple files containing specific word

To delete line which contains alsa-lib word from all .xml file, use
for f in *.xml; do sed -i '/alsa-lib/d' $f ; done

How to change linux console/terminal column width

To change linux console/terminal column width use stty, e.g. to change width to 180 column use
stty cols 180

Tensorflow on Windows

Get tensorflow installed and working on Windows.

Download docker toolbox for windows from https://www.docker.com/products/docker-toolbox
Use default selections, once installed it will create few shortcuts on your desktop.

Click on "Docker Quickstart Terminal" shortcut on desktop

Now press Windows key + R and type cmd, it will open new command terminal. Enter following in terminal

 docker-machine ssh default 

Start docker using below command

 docker run -it b.gcr.io/tensorflow/tensorflow:latest-devel 

If Its first time it will display following error and download it, which takes some time. Unable to find image 'b.gcr.io/tensorflow/tensorflow:latest-devel' locally latest-devel: Pulling from tensorflow/tensorflow

check tensorflow, by typing following

>>> import tensorflow as tf
>>> msg = tf.constant("Hello, World")
>>> sess = tf.Session()
>>> print sess.run(msg)
Hello, World
>>> 

To use windows shared folder with docker

Click "Oracle VM VirtualBox" shortcut on desktop.

Goto Settings-> "Shared Folders"

Click Folder+ Icon

Provide Folder Path, Folder Name, check Automount. e.g. I have folder name as dl_share

Now start docker by mounting share folder dl_share to /home/

docker-machine ssh default
sudo mkdir /win-share
sudo mount -t vboxsf dl_share /win-share
docker run -it -v /win-share:/home b.gcr.io/tensorflow/tensorflow:latest-devel

Convert audio from one format to other using ffmpeg

Convert wav format to dts format

 ./ffmpeg -i ~/sine_440Hz_2ch.wav -codec dts -strict -2 ~/sine_440Hz_2ch.dts 

Use mka container for above dts file

 ./ffmpeg -i ~/sine_440Hz_2ch.dts -vn -acodec copy -f matroska ~/sine_440Hz_2ch.mka 

Convert file from one container format to other

 ffmpeg -i input.mp4 -vcodec copy -acodec copy output.mkv 

Convert wav to ac3 format

 ./ffmpeg -i ~/sine_500Hz_2ch.wav -acodec ac3_fixed -ab 768k -ar 48000 test.ac3 

Use mka container for ac3

 ./ffmpeg -i test.ac3 -vn -acodec copy -f matroska ~/sine_500Hz_2ch-ac3.mka 

To grant all permission to android app

To grant all permissions to app, use -g as argument while installing with adb

 adb install -g myapp.apk 

Cross Compiling Linux kernel for ARM

Get latest stable kernel source code

 git clone https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 

To get kernel-next branch clone

 git clone https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git 

Get toolchain, e.g you can download linaro toolchain from Linaro toolchain for arm

set your path variable /path/to/linaro/binary/linaro/aarch64-unknown-linux-gnu_4.9-2014.05-01/bin

 export PATH=$PATH:/path/to/linaro/binary/linaro/aarch64-unknown-linux-gnu_4.9-2014.05-01/bin 

Setup defconfig file

 make ARCH=arm64 CROSS_COMPILE=aarch64-unknown-linux-gnu- O=output defconfig 

Make kernel image

 make ARCH=arm64 CROSS_COMPILE=aarch64-unknown-linux-gnu- O=output -j8 

To modify kernel configuration use

 make ARCH=arm64 CROSS_COMPILE=aarch64-unknown-linux-gnu- O=output menuconfig 

To save your modified defconfig file

 make ARCH=arm64 CROSS_COMPILE=aarch64-unknown-linux-gnu- O=output savedefconfig 

This will create defconfig file in output directory. Copy this file to your arch/arm64/configs directory

Adb over wifi, no USB cable required

Assumption is you are connected to device using UART for smoething similar so that you can run few commands on device

Find out the IP address of the Android device: Settings -> About tablet -> Status -> IP address. Remember the IP address, of the form #.#.#.#.

Steps on device
su
stop adbd
setprop service.adb.tcp.port 5555
start adbd

Steps on host
adb kill-server
sudo adb start-server
adb -a connect 192.168.1.64:5555