SHARED_LIBRARY_TO_ADD_TWO_NUMBERS

/*creating reqired Files*/
vim add.h
....
#ifndef add_h_
#define add_h_
extern int add(int , int );
#endif
...

 vim add.c
/*Definition of Shared Library*/
#include<stdio.h>
int add(int a,int b)
{
        puts("Hello,I am a shared library");
        return (a+b);
}
....
vim main.c
/*Executable code to run to call a shared Library Function*/
#include<stdio.h>
#include"add.h"
int main()
{
        int sum;
        int a,b;
        puts("Welcome to a shared library test...");
        printf("enter a and b \n");
        scanf("%d",&a);
        printf("entered a = %d \n",a);
        scanf("%d",&b);
        printf("entered b = %d \n",b);
        sum = add(a,b);
        printf("\nsum of a & b is = %d\n",sum);
        return 0;
}
COMMANDS USED :
1) gcc -c -Wall -Werror -fpic add.c // to display all types of errors while compiling.

2)gcc -shared -o libadd.so add.o // Compiling and creating libadd.so File with lib and .so as presfix and suffix to repesent it is shared library
 
/* YOU WILL FIND A libadd.so file in the same directory Which is an ELF - executable and linkable file*/

/*compiling library add and creating an ELF as test file to run your code
3)gcc -L/home/jarvis/shrdlib -Wall -o test main.c -ladd
   ls
  ./test
   echo $LD_LIBRARY_PATH
   LD_LIBRARY_PATHi /home/jarvis/shrdlib
4)LD_LIBRARY_PATH=/home/jarvis/shrdlib:$LD_LIBRARY_PATH  // Loading in to kernel of the current path into loader
 
5)   export LD_LIBRARY_PATH=/home/jarvis/shrdlib:$LD_LIBRARY_PATH //exporting library so that linker finds it in default paths in the kernel//
  
./test  __//running//