PA_CreateResource

version 2003

PA_CreateResource (resFile; kind; resID; name; resData; dataSize) → short

The routine PA_CreateResource adds a resource of type kind and unique number ID to the resource file resFile . The resource will be filled with the data pointed by resData .

Pass in resFile the reference number of the file to access (obtained with PA_CreateResFile , PA_OpenResFile , PA_GetDatabaseResFile ).

In kind , you pass the 4-bytes type of the resource ('TEXT', 'PICT', 'toto').

Pass in resID the unique ID of the resource you want to create. If you pass -1 in resID , then 4th Dimension will find a unique ID for you.

In name , pass a string and the name of the resource (it can be a null string). Depending on default settings or on previous calls to PA_UsePStrings or PA_UseCStrings , name will be either a Pascal or ANSI C string.

In resData , pass a pointer to the data of the new resource and its size in bytes in dataSize .

If the resources has been successfully created, PA_GetLastError is set to eER_NoErr and the routine returns the ID (it will be equal to resID if it was not -1).

If a resource of the same kind and the same ID already exists, PA_CreateResource overwrites it without generating any error.

(1) Wrap the routine to ensure that we do not overwrite an existing resource. To do this, use PA_GetResourceHandle that returns 0 if the specified resource does not exist.

   short myCreateResource(short resFile, unsigned long kind, short resID, char *name, char *data, long size)
   {
   // if resID is -1, 4D will find an unique ID for us. We do not care in this case.
      if(resID != -1)
      {
         PA_Handle h = PA_GetResourceHandle(resFile, kind, resID);
         if(h) // the same resource already exists. Return the error, but first release memory
         {
            PA_DetachResource(resFile, h);
            PA_DisposeHandle(h);
            MyGenerateError (kMY_ERROR_CODE_RESOURCE_EXISTS);
            return -1; // this must be checked in the calling routine
         }
      }
   // We are here: the resource does not exists, or resID is -1.
      return PA_CreateResource(resFile, kind, resID, data, size);
   }

(2)Create a new resource based on a private structure (using the previous wrapper)

   typedef struct
   {
      long   f1;
      long   f2;
      long   f3;
      long   f4;
   } AStructure;
   #define   
 
   short Add_AStructureResource(short resFile, AStructure *toAdd, char *name)
   {
      return myCreateResource(resFile,
         'Tißo',
         -1, // let 4D find an ID and return it
         name,
         (char *) toAdd,
         sizeof(AStructure));
   }

PA_CreateResourceFromHandle .

Use PA_GetLastError to see if an error occurred