title: Typedeffed struct is undefined although it is defined
body: <p>I'm receiving an error message from the compiler indicating (it's an embedded C compiler):</p>
  
  <p>Error[Pe020]: identifier "MPTR" is undefined in myflash.h (see code below)</p>
  
  <p>I'm using a typedeffed struct called MPTR. The code is:</p>
  
  <pre><code>//datahandler.h
  #ifndef DATAHANDLER_H
  #define DATAHANDLER_H
  
  #include "enet_uip_ap01.h"
  
  typedef struct _MPTR {
  
  unsigned int flash_start;
  unsigned int flash_pagestart;
  
  unsigned short rom_start;
  unsigned short rom_nextrecord;
  unsigned short rom_lastrecord;
  } MPTR;
  
  ...etc
  </code></pre>
  
  <p>I want to forward declare a function using an MPTR argument in another header:</p>
  
  <pre><code>//myflash.h
  #ifndef MYFLASH_H
  #define MYFLASH_H
  
  #include "enet_uip_ap01.h"
  
  
  unsigned char FLASH_StorePage(MPTR *mptr, unsigned short addr, unsigned int flag);
  </code></pre>
  
  <p>Both headers: "datahandler.h" and "myflash.h" are included in "enet_uip_ap01.h". However, the above function declaration throws a compilation error.</p>
  
  <p>Most likely it is a plain basic C language issue and it's a shame that I don't know but I'm out of ideas how to solve it. I'd be very glad if someone could point me to my error. Thank you!</p>
  
  <p>EDIT: placed additional code here:</p>
  
  <pre><code>//enet_uip_ap01.h
  #ifndef ENET_UIP_AP01_H
  #define ENET_UIP_AP01_H
  
  //....other not relevant includes here...
  #include "datahandler.h"
  #include "myflash.h"
  
  #endif
  </code></pre>