How to compile a C program in gcc which has header files?

Question

I want to compile a C program in gcc which has my 2 header files.

I am using the command:

gcc UDP_Receive.c -o UDP_Receive -lm

to compile it but I get an error stating "UDP_Data.h: No such file or directory"

How can I tell the compiler to include these header files?

Header Files:

#include "UDP_Data.h"

#include "Crypt.h"

Thanks, Ritesh

Solution 1

Use -Idirectory to add include paths, or make your #include statement use relative paths.

EDIT: Also be aware that #include filenames are case sensitive on many platforms.

EDIT2: Use #include "UDP_Data.h" not #include <UDP_Data.h>

Solution 2

You have told the compiler to include that file, with a line like this:

#include "UDP_Data.h"

the problem is that the compiler can't find that file, and don't forget that some platforms are case sensitive when it comes to filenames so "UDP_data.h" is not the same file as "UDP_Data.h". The compiler will serach in a few places by default, but you will need to add extra directories to its search by using command line options. The exact option will depend on the compiler, for gcc it's:

-I<directory>

Comments

[Ritesh Banka]

My header files are in the same location as my source code files.

[Ritesh Banka]

My header files are in the same location as my source code files. Could you please post a detailed example to walk me through the compilation process. Thanks

[Erik]

Is the filename exactly UDP_Data.h? Not e.g. UDP_data.h?

[Ritesh Banka]

Yes, the file name is "UDP_Data.h"

[Skizz]

@Jim: How would you get that error if that line wasn't in the source file? (Apart from extra command line options of course!)

[Erik]

Are you using #include "" and not #include <>?

[Ritesh Banka]

Yes, I am including the headers in ""

[Erik]

Please edit your post and copy-paste any #include statements you have.

[Ritesh Banka]

#include "UDP_Data.h" #include "Crypt.h"

[Erik]

According to the information you have given, this should work. If UDP_Data.h is in the same directory as UDP_Receive.c, and the filename is correct, this works. Doublecheck the filenames (look for hidden "weird" characters) both in the #include and the actual filename.