Does the program execution always start from main in C?

Question

Must program execution start from main, or can the starting address be modified?

#include 

void fun();

#pragma startup fun

int main()
{
            


        

Answer 1

As far as the ISO C Standard is concerned, the entry point for a C program is always main (unless some implementation-defined feature is used to override it) for a hosted implementation. For a "freestanding implementation" (typically an embedded system, often with no operating system), the entry point is implementation-defined.