#include<stdio.h>
#include<conio.h>
void main()
{
  clrscr();
  printf("hai");
 getch();
}

#include<iostream.h>
#include<conio.hg>
int main()
{
clrscr();
printf(" \t  hi this is sriram \t \n");
getch();
return 0;
}

this can be achieved by file handling

#include<stdio.h>
void main()
{
FILE *fp;
char ch;
clrscr();
fp=fopen("file.c","r");
ch=getc(fp);
while(ch!=EOF)
{
putchar(ch);
ch=getc(fp);
}
getch();
}

The most simple possible program printing itself on windows :
main()
{
char path[255];
sprintf(path,"cmd.exe /c type \"%s\"",__FILE__);
system(path);
}

on Unix you just use "cat" instead of "type" and necessary
fun to call bash command from c program.

This can be achieved by file handling,
If r is the name of this file;The following codewil print 
this prg.

#include<stdio.h>
void main()
{
FILE *fp;
char ch;
clrscr();
fp=fopen("file.c","r");
ch=getc(fp);
while(ch!=EOF)
{
putchar(ch);
ch=getc(fp);
}
getch();
}

main(a){printf(a,34,a="main(a){printf(a,34,a=%c%s%c,34);}",34);}

copied from somewhere, but it works

#include<stdio.h>

char*s="char*s=%c%s%c;main(){printf(s,34,s,34);}";
main()
{
printf(s,34,s,34);
}