asad akbar aakbar5

## enum as bitfield
By default enum can't be as bitfield

typedef enum _type_ {
CAT = 0,
DOG,
UNKNOWN
} TYPE;

typedef struct _animal {
TYPE type : 2;

## Filter lines starting with a specific keyword
grep -Ev '^(X|Y|Z)' /path/to/your/file

-E is to use extended regular expressions.
^ matches the beginning of the line.
(X|Y|Z) means lines start with X or Y or Z.

## debugging on embedded hardware
- hardware is embedded linux
- Application is cross compiled

## bootconsole[uart0] disabled
- linux boot hanged after showing "bootconsole[uart0] disabled".
- Make sure that boot args are having console=ttySX,115200n8
- where X in ttySX is the number of the device. It can be ttyS0, ttyS1 and so on.

## error: couldn't mount as ext3 due to feature incompatibilities
- Use menuconfig to enable options in FileSystem to match filesystem of your storage device where rootfs is placed

## error: couldn't mount because of unsupported optional features (240)
- Add rootfstype=ext4 to bootargs to get rid of this

## kernel panic
- Make sure that you got /sbin/init (A bash script) onto your rootfs.
- Make sure that /sbin/init is placed after chmod +x.

## Check shared library dependencies of a program executable
objdump -p /path/to/program | grep NEEDED

ref: http://ask.xmodulo.com/check-library-dependency-program-process-linux.html

## Mount ssh folder
on local host install sshfs via sudo apt-get install sshfs

mkdir /folder/on/local/machine/used/for/mounting
sshfs <user-name>@<machine-name>:/<path/to/folder/to/be/mounted> /folder/on/local/machine/used/for/mounting

## Ubuntu 14.04 sound problem
Problem: Ubuntu 14.04 was playing noise alonwith mp3 file.
Solution: Add 'options snd-hda-intel vid=8086 pid=8ca0 snoop=0' at the end of file /etc/modprobe.d/alsa-base.conf.
	By default enum can't be as bitfield

	typedef enum _type_ {
	CAT = 0,
	DOG,
	UNKNOWN
	} TYPE;

	typedef struct _animal {
	TYPE type : 2;
	grep -Ev '^(X\|Y\|Z)' /path/to/your/file

	-E is to use extended regular expressions.
	^ matches the beginning of the line.
	(X\|Y\|Z) means lines start with X or Y or Z.
	- linux boot hanged after showing "bootconsole[uart0] disabled".
	- Make sure that boot args are having console=ttySX,115200n8
	- where X in ttySX is the number of the device. It can be ttyS0, ttyS1 and so on.
	- Make sure that you got /sbin/init (A bash script) onto your rootfs.
	- Make sure that /sbin/init is placed after chmod +x.
	objdump -p /path/to/program \| grep NEEDED

	ref: http://ask.xmodulo.com/check-library-dependency-program-process-linux.html
	on local host install sshfs via sudo apt-get install sshfs

	mkdir /folder/on/local/machine/used/for/mounting
	sshfs <user-name>@<machine-name>:/<path/to/folder/to/be/mounted> /folder/on/local/machine/used/for/mounting
	Problem: Ubuntu 14.04 was playing noise alonwith mp3 file.
	Solution: Add 'options snd-hda-intel vid=8086 pid=8ca0 snoop=0' at the end of file /etc/modprobe.d/alsa-base.conf.