Thread: calling functions: exit and return

In C program I have a function:

Code:

void eg1()
{
	if (i==1){
		exit(1)
	}
}

main(){

eg1();

}

Return type of eg1 is void, so does it make sense/valid to do exit(1) inside it. If there is a faliure in eg1, then it will come back to main immediately or the whole progam stops? Also, exit(1) and return 1; are same thing?