c programming run without header file
write example given below.
void main()
{
clrscr();
printf("hello");
getch();
}

If we save our program with .c extention before compiling it, the compiler with automatically include the header files. for eg-
First we save our program with sum.c and then complile it. It will not show any error.

After compile one time source code with the help of header files then we can again run that prog. without using header files.

You cannot run a C program without header files. By default some compilers include header files like stdio.h but in the above program, functions getch() and clrscr() use header files which should be mentioned by the programmer. If the above program should run then the programmer should implement the functions inside the code.

The above program will not work.because the getch() is declared in conio.h and printf() require stdio.h .without header files we can't run this program.

yes a c program runs without including header files..above program would run correctly because by default the c complier includes some header file..so clrscr() and getch() in above program would work without header files..

but in case of c++ it is not so...
there we have to include header files

we can run C program without includeing header file.
for this after writng code we will have to save the program
after saving the program if we excute it program will work as the compiler will include header file by default.
it will also work in case of c++
eg
void main()
{
int a,b,c;
printf("Enter the values of a and b ");
scanf("%d %d",&a,&b);
c= a+b;
c++
printf("The value is %d",c);
}

you can run a c program without header files like stdio.h and
conio.h.It is not necessary to save them befor running.
In c++ each header file must be provide by the user execpt the one
below:
main()
{int a,b;
}

if you try to add getch() with out
adding conio.h it will show you error

In case of c ,, yeah its possible...
The nly thing id u hv to save the program with extension .c, then n only then it woll include some standard header files... lik stdio.h,, conio.h,,,

yes if we save our proram with .c then its include bydefault stdio.h header file so its works as hiddenly

only printf and scanf functions work. Does any other function work without adding the header file?

The above program will not work.because the getch() Funtion is declared in conio.h and printf()Function is require stdio.h .without header files we can't run this program.

The above program will not work.because the getch() function is declared in conio.h and printf() function require stdio.h .without header files we can't run this program.

The above program will not work.because the getch()Function is declared in conio.h and printf() Function require stdio.h .without header files we can't run this program.

This program will not be even compile but if you want to get the output of it so just save it with [.c] extension then it'll compile as well as give you output.

Yes, It'll run ....because by default C compier adds header files to the code when its object file is created "prog_name.obj"

But keep in my mind it need to save 1st with ".c" extension bcz without saving the noname.cpp uses CPP compiler that cannot do so...

A program can run without including .h files, only if your program contains no predefined library calls like printf ,scanf and others like malloc included. You have to implement your own program for this predefined library.This will be helpful only for small programs.

if we write a program without main function the program will compile without error but during the run time the compler will search for main function so it will not display the output

without header file no c program can execute. If we write a c code with out header file and save it with .c extension the compiler will automatically include the header files.
e.g:

void main()
{
printef("hello"):
}

will run with no error if we name it as sample.c first then compile

we write a c program witout using header file.The program work properly ,because we save a program with .c before compile the program it will work.bydefaut compiler have a stdio.h and conio.h header file's

We cam write a program with out header file please follow it
$ gedit main.c
write the below program

void main()
{
if(printf("This is test")){}
}
save and quit gedit

[Basanta@localhost trial]$ gcc main.c
main.c: In function ?main?:
main.c:3:4: warning: incompatible implicit declaration of built-in function ?printf?
[Basanta@localhost trial]$ ./a.out

you will get the output

without header files we can run c program.if you save your progarm .c before compilation then header file is not require,and you compile your program whitout save then error occur and in this condition you written header files.

If you are saving your file with .c extension then compiler automatically includes the require header files, but this would not work in case of file saved with .cpp extension.

We can't run a c program with-out Header file. but we run it an another process.

without header files we can run c program.if you save your progarm .c before compilation then header file is not require,and you compile your program whitout save then error occur and in this condition you written header files.

It will not compile the program without using the header file, if we are saving the file with .CPP extension.

yes, any c program can run without header files, by directly using the assembly language support,which can be effectively used to replace the standard functions.

e.g in Turbo C++

void main()
{ char *ch="Hi!.How are you?$"
asm{
push ax;
push dx;
mov dx,[&ch];
mov ah,0x09;
int 0x21;
pop dx;
pop ax;
}
}

and the output is:
Hi!.How are you?

yeh..its really working..thanx. it helped me a lot..

if we save the programm with .ccp extension ....then the programm will be run without header file.....

yes it is very easy to written a programme without header file...
main()
{
int a,b,c;
a=5;
b=5;
c=a+b;
printf("%d",c);
}

hello guys , ijust wanna say 2 posssibilities--
1.our os is made in c,,so there are predefined compilers-
2.there are many compilers which use predefined header files

yes in class of c, this program will work fine .coz the complier itself by default add the header files like stdio.h and conio.h .but in case of c++ the program is non executable it will ask for the prototype.

the above program will work correctly if the program is saved with filename.c ,.c extension is required if you don't want to include headerfile,if you make .cpp extension this program will give error during compilation.

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