why there is a void?

[Justin Klisk]

i'm new in cprogramming.that's why i'm here?so,certain program there have a void and certain program there don't have void thing. what is it all about? it's not returning the value back to it.
hope to know it as soon. "VOID"

[Shadow]

Well...void main is bad. But, I suppose you could be talking about a function not returning a value to the calling function.

Which are you talking about?

[justin klisk]

well,yes i'm talking about the function that not returning a value to the callling function.

could u give me a example that i can refer to?plss...
just two program,with void main and the other without void main.
thanks a lot..i will be here today. Important.

[Shadow]

#include <stdio.h>

void main ( void )
{
	printf("Hello World!\n");
	return;
}

#include <stdio.h>

int main ( void )
{
	printf("Hello World!\n");
	return 0;
}

Don't use void main!

#include <stdio.h>

int ReturnsSomething ( void );
void DoesntReturnSomething ( void );

int main ( void )
{
	printf("Checking return status of functions..\n");
	printf("Press any key..\n\n");
	getchar();
	if ( ReturnsSomething() == 0 )
	{
		printf("He was nice.\n");
	}
	else
	{
		printf("He wasn't so nice!\n");
	}

	if ( DoesntReturnSomething() == 0 )
	{
		printf("He was nice.\n");
	}
	else
	{
		printf("He wasn't so nice.\n");
	}
	return 0;
}

int ReturnsSomething ( void )
{
	return 0;
}

void DoesntReturnSomething ( void )
{
	return;
}

Void main doesn't return a status. How can your operating system check the return status of a program that doesn't return a status? Your operating system expects you to return something, if you don't it gets confused, and it's also undefined behavior - that's not good.

Search the board using the search function to read more on this.

- edit -
Heh, I'm not sure if that compare program will compile or not... ah well, search for void main ...and you got your 2 examples.

Good luck.