Can you write a "C" program with out main() ....???

/*
The answer is YES. Try the following code
*/
#include<stdio.h>
#define decodes(s,t,u,m,p,e,d) m##s##u##t
#define begin decode (a,n,i,m,a,t,e)

int begin()
{
        printf("Hello");
}

// This is possible in Turbo C. In linux we've anothe way.


Here is how it works once we say define we need to understand that
#define x y
then ‘x’ ix replaced by ‘y’
similarly in this case
#define begin decode(a,n,i,m,a,t,e)
decode(a,n,i,m,a,t,e) is replaced by m##a##i##n
bcoz s is replaced by a,t by n,u by i and so on
s->a
t->n
u->i
m->m
p->a
e->t
d->e
now the statement becomes
void m##a##i##n
And u must be knowing that ## is used for string concatenation so it becomes
“main”
finally the code crops down to
void main()
{
printf(“hello”);
}

About pointers and Arrays.

http://sravanelectronics.blogspot.com/2013/02/pointers-and-arrays.html

realloc()

The following example illustrates the use of calloc() function in C.

The following example illustrates the use of malloc() function in C.

Is main() user defined function or pre-defined function?????

The main function is a user implemented function whose prototype is pre -defined by compilers (known as implementations in the C standard) and used as the entry point of a C program, as per ISO/IEC 9899:TC2 Section 5.1.2.2.1:

The function called at program startup is named main. The implementation declares no prototype for this function. it shall be defined  with a return type of int and with no parameters

int main(void) { /* ... */ }

or with two parameters (referred to here as argc and argv, though any names maybe used, as they are local to the function in which they are declared):

int main(int argc, char *argv[]) { /* ... */ }

or equivalent; or in some other implementation-defined manner.

The reason why it is prototyped by the compiler is simple: the compiler needs to know where to start so it can emit a proper executable that can be run. (Of course, if you are writing a library, it is perfectly fine to not have a main function - and in fact you shouldn't have one).

C compilation process video

http://www.youtube.com/watch?feature=player_embedded&v=gUKXew-0L1I

Understanding the Execution of c program

Linux Journal

http://www.mediafire.com/?avr4ov8ync66t79

Linux & Open Source Genius Guide

http://www.mediafire.com/?3lcort3nb471v6n

In Detail about stack and Heap in C language

http://www.mediafire.com/view/?n5tivf5vn1wn284

Important Programs in C-language

http://www.mediafire.com/view/?62bhl961na9i37h

Almost all "for" logics in C language.

http://www.mediafire.com/view/?exosu8qoda88boh