c - Header file help & structures -

i have header file, dimensions.h , in it:

#ifndef dim_h #define dim_h  typedef struct dimensions {     int width;     int height; } dim;  dim * getheader (file * fp);  #endif 

from here have c file has this:

#include "dimensions.h" . . . dim *  getheader (file * fp) {     char s[1024];     struct dimensions * d = (struct dimensions *)malloc(sizeof(dimensions));      if (fgets(s, sizeof(s), fp) != null)     {         printf("%s", s);         d->width = atoi(strtok(s, " \n\0"));         d->height = atoi(strtok(null, " \n\0"));     }      return d; } 

but when run errors dimensions undeclared. played around code changing dimensions dim (still not understanding 2 name 'scheme'.

struct dim * d = (struct dim *)malloc(sizeof(dim)); 

then errors d->width , d->height saying it's dereferencing pointers incomplete types, swapped -> . , error request member width/height in not structure or union.

so not sure what's going on, might simple i'm missing if that'd awesome.

thanks!

part 1: dimensions undeclared

see line in original code?

struct dimensions * d = (struct dimensions *)malloc(sizeof(dimensions)); 

if use struct dimensions somewhere, use everywhere. change sizeof to

sizeof(struct dimensions) 

and dimensions undeclared should go away.

part 2: dim version

your code:

struct dim * d = (struct dim *)malloc(sizeof(dim)); 

when typedef struct {...} dim, need refer dim - not struct dim.

dim * d = (dim *)malloc(sizeof(dim)); 

part 3: swap -> .

use -> when left side pointer structure, , . when left side structure.

tl;dr

struct dimensions * d = (struct dimensions *)malloc(sizeof(struct dimensions)); 

should fix code.