Virtual box Full screen mode for debian

1. Login as root;
2. Update your APT database with apt-get update;
3. Install the latest security updates with apt-get upgrade;
4. Install required packages with apt-get install build-essential module-assistant;
5. Configure your system for building kernel modules by running m-a prepare;
6. Click on Install Guest Additions… from the Devices menu, then run mount /media/cdrom.
7. Run sh /media/cdrom/VBoxLinuxAdditions.run, and follow the instructions on screen

Install nodejs , npm and websocket in Debain wheezy

Installing npm and websocket is not so easy in Debian wheezy. You can make use of the below steps to install websocket and npm in Debian wheezy.

1) Install nodejs using the Debian package manager 

apt-get install nodejs

2) npm does not come with Debian package management system. Still there is a way 

curl https://www.npmjs.com/install.sh | sh

3) To install websocket, you need to upgrade to the latest version of nodejs and node-gyp package. You can install latest version of nodejs using nmp

npm cache clean -f

npm install -g n

n stable

n 4.7.2

4) Install node-gyp package using npm

npm install -g node-gyp

5) Finally install websocket using npm

npm install webscoket

P.S.

npm makes it easy for JavaScript developers to share and reuse code, and it makes it easy to update the code that you're sharing.

Compiling and Running 32 bit UML on 64 bit Debian operating system

Steps followed
============
1) apt-get install uml-utilities
2) sudo apt-get install gcc-multilib
C_INCLUDE_PATH=/usr/include/$(gcc -print-multiarch)
http://stackoverflow.com/questions/12591629/gcc-cannot-find-bits-predefs-h-on-i686
Since we are compiling the UML kernel for 32 bit in 64 bit operating system, we need a gcc-multilib package to solve the library issues
3) #include<sys/stat.h> in ./arch/um/os-Linux/mem.c
http://stackoverflow.com/questions/5918539/c-warning-implicit-declaration-of-function-fchmod
4) The below patch needs to be applied
 In some cases gcc >= 4.5.2 will optimize away current_thread_info().
To prevent gcc from doing so the stack address has to be obtained
via inline asm.

LKML-Reference: http://marc.info/?i=201104132150.05623.richard@...>

Acked-by: Kirill A. Shutemov <kirill@...>
Signed-off-by: Richard Weinberger <richard@...>
---
 arch/um/include/asm/thread_info.h |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/arch/um/include/asm/thread_info.h b/arch/um/include/asm/thread_info.h
index e2cf786..5bd1bad 100644
--- a/arch/um/include/asm/thread_info.h
+++ b/arch/um/include/asm/thread_info.h
@@ -49,7 +49,10 @@ static inline struct thread_info *current_thread_info(void)
 {
         struct thread_info *ti;
         unsigned long mask = THREAD_SIZE - 1;
-       ti = (struct thread_info *) (((unsigned long) &ti) & ~mask);
+       void *p;
+
+       asm volatile ("" : "=r" (p) : "0" (&ti));
+       ti = (struct thread_info *) (((unsigned long)p) & ~mask);
         return ti;
 }

--
1.7.4.2
http://sourceforge.net/mailarchive/message.php?msg_id=27397459

Compilation steps
================
1) make mrproper ARCH=um
2) make menuconfig ARCH=um SUBARCH=i386
http://uml.devloop.org.uk/faq.html
3) make ARCH=um SUBARCH=i386

pulseaudio[1378]: lock-autospawn.c: Cannot access autospawn lock

Sometimes we used to face problems in getting into GUI Mode in debian systems.

Try to see the error messages logged in syslog

bash-3.1#  tailf /var/log/syslog

In case if you are getting the below error messages

Jan 14 04:37:45 debian pulseaudio[4062]: [autospawn] lock-autospawn.c: Cannot access autospawn lock.

Jan 14 04:37:45 debian pulseaudio[4062]: [pulseaudio] main.c: Failed to acquire autospawn lock

Here are the steps to solve it

1)Change the user permission of the folder from root to appropriate user as below

sudo chown -R user:user /home/user

For example

===========

The name of the user is "labuser".

Check the owner of the folder "/home/labuser"

bash-3.1# ls -lrt /home/

drwxr-xr-x 25 root root           4096 Jan 13 18:36 labuser

here the folder is owned by root. We need to change it as

sudo chown -R labuser:labuser /home/labuser

bash-3.1# ls -lrt /home/

drwxr-xr-x 25 labuser labuser           4096 Jan 13 18:36 labuser

2) Switch to labuser mode

bash-3.1# su labuser

3) Execute the below command

start-pulseaudio-x11

bash-3.1#  start-pulseaudio-x11

The command should run successfully.

4) In case if you are getting the below error messages

E: [autospawn] core-util.c: Failed to create random directory /tmp/pulse-1cadfldalelalrfmmad: Permission denied

E: [autospawn] core-util.c:Failed to symlink /home/labuser/.pulse/1c4f1cadfldalelalrfmmad

E: [autospawn] lock-autospawn.c: Cannot access autospawn lock

E: [pulseaudio] main.c: Failed to acquire autospawn lock

Change the permission of /tmp folder from root mode

bash-3.1#  chmod 777 /tmp

5) Reboot the system

6) Now you could able to login the GUI for a user successfully

Reference
http://askubuntu.com/questions/349767/cant-start-pulseaudio-ubuntu-12-04-cant-use-usb-headset