header.h: No such file or directory even though source and header are in same directory

Question

I have made a header and a source but I don't know how to link them up. I looked it up on the web but the commands provided didn't work (or I wouldn't be here :) ).

To compile it (if you use GCC):

Header:

$ gcc -c whatever.h -o whatever.o

Source:

$ gcc -c sample.c -o sample.o

To link the files to create an executable file:

$ gcc sample.o whatever.o -o sample

What did I do wrong. I am using geany for writing (compile error is here) but the commands are executed on a terminal in the same directory. can anybody give me the build commands for geany so whenever I want to include a header I can just compile and run?

@CoderGuy You're not supposed to compile headers in the first place. — Biffen, Feb 12 '15 at 10:41
@biffen i got it from here: http://stackoverflow.com/questions/2831361/how-can-i-create-c-header-files — BRHSM, Feb 12 '15 at 10:45
@CoderGuy And which part of that told you to compile a header file? — Biffen, Feb 12 '15 at 10:47
@CoderGuy You mean where it says `gcc -c whatever.c -o whatever.o`? Note that `whatever.c` != `whatever.h`. — Biffen, Feb 12 '15 at 10:54

score 8 · Accepted Answer · answered Feb 12 '15 at 10:34

8

Good and the right way would be to

sample.c

#include "header.h"

and compile

gcc sample.c -o ob

answered Feb 12 '15 at 10:34

Gopi

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How would that be in geany (Build and compile commands). that would be easyer – BRHSM Feb 12 '15 at 10:36
what does the f2.c and f1.c stand for? in geany build commands it's all like "%f" and stuff – BRHSM Feb 12 '15 at 10:43
@CoderGuy Let me not confuse you please include the header in .c file compile and run.. – Gopi Feb 12 '15 at 10:45
but the header is a .h file – BRHSM Feb 12 '15 at 10:45
I did, it says that the file is not found but it is in the same directory as the c file – BRHSM Feb 12 '15 at 10:46
@CoderGuy *How*, *exactly*, do you include it? – Biffen Feb 12 '15 at 10:56
@CoderGuy Show your .c and .h file and how you are including the header.. Nothing to do with geany. – Gopi Feb 12 '15 at 11:04
@CoderGuy I compiled built and ran in geany .. I don't get your problem – Gopi Feb 12 '15 at 11:13
i use `#include ` – BRHSM Feb 12 '15 at 14:49
2

@CoderGuy There you go!! Please use `#include "header.h"` .. Use double quotes instead of `<` `>` brackets – Gopi Feb 12 '15 at 14:50
@CoderGuy Is your header called `header.h` or `whatever.h`? – Biffen Feb 12 '15 at 14:51
well, non of the above, but it contains my full name so I don't want to type it here. anyway you can use whatever you want for your example, I'll probably understand – BRHSM Feb 12 '15 at 15:11
@CoderGuy You need to understand the difference between `#include` and `#include "header.h"` Is your issue resolved or not? Hold on... your need to include `#include "yourfullname.h"` Whatever your full name is .... – Gopi Feb 12 '15 at 15:13
so not with the `<>` thing – BRHSM Feb 12 '15 at 15:25
@CoderGuy NO !! with `" "` – Gopi Feb 12 '15 at 15:26

Sourav Ghosh · Answer 2 · 2015-02-12T11:07:30.857

4

Thumb Rule:

header files [.h] are for #includeing
source files [.c] are for compiling and linking together to create the executable.

Once you've #included your header file in a .c file, there's no need to compile the header file and produce an object file.

FYI, you can check the effect of #include-ing the header file by running

gcc -E sample.c

and hope you'll understand why you need not compile and link the header file separately.

EDIT:

if you have a sample.c and whatever.h, to produce and run the binary, simply do

#include "whatever.h" in the top of sample.c
gcc -o sample sample.c
./sample

edited Feb 12 '15 at 11:07

answered Feb 12 '15 at 10:37

Sourav Ghosh

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@CoderGuy Sorry, no. But how that is related to this? – Sourav Ghosh Feb 12 '15 at 10:47
@CoderGuy Your issue has nothing to do with the `geany` or anything. Kindly correct the actions, it'll work. :-) – Sourav Ghosh Feb 12 '15 at 10:54
@Biffen Whoops !! Typo. Thanks. – Sourav Ghosh Feb 12 '15 at 11:07

score 2 · Answer 3 · answered Oct 01 '20 at 11:34

2

if you include header file by:

#include <header.h>

it will give this error.

Instead you can write as given below:

#include "header.h"

answered Oct 01 '20 at 11:34

Shiv Buyya

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header.h: No such file or directory even though source and header are in same directory

3 Answers3