C Program without main() function

In the C programming language, the main() function is the entry point of a program. It is where the execution of the program starts. Therefore, it is not possible to write a valid C program without a main() function. The presence of main() is mandatory for the program to compile and run successfully.

Every C program must have a main() function defined as follows:

int main()
    // Code goes here
    return 0;

Within the main() function, you can write the code that you want to execute when the program starts running.

Note that some compilers or development environments may provide alternative entry points or startup code, but they internally call the main() function. So, although it might appear as if you are not using main(), it is still there behind the scenes.