C forward declaration of struct in header

Question

I am trying to pass `struct` pointer in function. I have a `typedef` in file1.h, and want to only include that header to file2.c, because file2.h only need pointer. In C++ I would just write like I did here, but using C99 it doesn't work. If someone has any suggestions how to pass `struct` pointer without full definition it would be very appreciated. Compiler - gcc. file1.h ``` typedef struct { ... } NEW_STRUCT; ``` file2.h ``` struct NEW_STRUCT; void foo(NEW_STRUCT *new_struct); //error: unknown type name 'NEW_STRUCT' ``` file2.c ``` #include "file2.h" #include "file1.h" void foo(NEW_STRUCT *new_struct) { ... } ```

Accepted Answer

I think you just have to name your structure, and do a forward declaration of it and after re typedef it.

First file:

```
 typedef struct structName {} t_structName;
```

Second file:

```
  struct stuctName;
  typedef struct structName t_structName
```

C forward declaration of struct in header

Solution

Problem