Embedded Systems Articles-3

Dynamic Allocation and Pointer:
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What Are Pointers
Pointers are basically the same as any other variable. However, what is different about them is that instead of containing actual data, they contain a pointer to the memory location where information can be found. This is a very important concept. Many programs and ideas rely on pointers as the basis

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Array Of Structures:
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C Structure is collection of different datatypes ( variables ) which are grouped together. Whereas, array of structures is nothing but collection of structures. This is also called as structure array in C.
Example:
This program is used to store and access “id, name and percentage” for 3 students. Structure array

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Socket System Calls:
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Let’s look at a call to socket() (the includes required are sys/types.h and sys/socket.h):
int socket(int domain, int type, int protocol);
A successful call to socket() returns a descriptor that will be used for end-point communication. The first argument, domain, specifies a communication domain — the protocol famil

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While Loop:
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/*C program to demonstrate the working of while loop*/
#include <stdio.h>
int main()
{
int number,factorial;
printf("Enter a number.\n");
scanf("%d",&number);
factorial=1;
while (number>0)
{
factorial=factorial*number;
--number

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A Small notes on Internet Protocol (IP):
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TCP/IP includes a wide range of protocols which are used for a variety of purposes on the network. The set of protocols that are a part of TCP/IP is called the TCP/IP protocol stack or the TCP/IP suite of protocols. The Network layer is also know as the internet layer. The internet layer is a group of internetworking m

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Linux Process creation:
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Process Descriptors:
The kernel maintains info about each process in a process descriptor, of type task_struct.
See include/linux/sched.h
Each process descriptor contains info such as run-state of process, address space, list of open files, process priority etc…
Process State:
Consists of an array of mutually ex

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A small note on Protocol:
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Application layer is the top most layer in OSI and TCP/IP layered model. This layer exists in both layered Models because of its significance, of interacting with user and user applications. This layer is for applications which are involved in communi

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A small note on Linux Kernel:
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kernel is the innermost portion of the operating system, where user interface is the outer portion. kernel is the core internal, the software that provides the basic services for all the other parts of the system, manage hardware and distributes system resources.
applications running on the system communicate with th

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C Structure in Detail:
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C Structure is a collection of different data types which are grouped together and each element in a C structure is called member.
• If you want to access structure members in C, structure variable should be declared.
• Many structure variables can be declared for same structure and memory will be allocated for each

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C Pointers in Detail:
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Pointers have many but easy concepts and they are very important to C programming. There are following few important pointer concepts which should be clear to a C programmer:
Passing pointers to functions in C:
C programming language allows you to pass a pointer to a function. To do so, simply declare the function pa

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A note on Linux Signal:
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signal:
Signals are software interrupts.
A robust program need to handle signals. This is because signals are a way to deliver asynchronous events to the application.
A user hitting ctrl+c, a process sending a signal to kill another process etc are all such cases where a process needs to do
signal handling.
Li

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