Wiki Page Content

Revision 2 as of 2010-08-22 20:31:17

Clear message

DRAFT

SDL_RWread

Use this function to read from a data source -or- *call the function pointed to by an SDL_RWops structure's read member.*

Syntax

size_t SDL_RWread(struct SDL_RWops* context,
                  void*             ptr,
                  size_t            size,
                  size_t            maxnum)

Function Parameters

context

a pointer to an SDL_RWops structure

ptr

*a pointer to an area of memory to read data into*

size

*the size of each block of memory to read*

maxnum

*the maximum number of memory blocks to read (it may read less)*

Return Value

Returns the number of objects read, or 0 at error or end of file; call SDL_GetError() for more information.

-or-

*Returns the number of memory blocks read, or -1 if the read failed*; call SDL_GetError() for more information.

Code Examples

*

#include <stdio.h>
#include "SDL_rwops.h"
int main()
{
  int blocks;
  char buf[256];
  SDL_RWops *rw=SDL_RWFromFile("file.bin","rb");
  if(rw==NULL)
  {
    fprintf(stderr,"Couldn't open file.bin\n");
    return(1);
  }

  blocks=SDL_RWread(rw,buf,16,256/16);
  SDL_RWclose(rw);
  if(blocks<0)
  {
    fprintf(stderr,"Couldn't read from file.bin\n");
    return(2);
  }

  fprintf(stderr,"Read %d 16-byte blocks\n",blocks);
  return(0);
}

*

Remarks

*
This is not a built in function. This is a C macro that calls whatever function happens to be in the 'read' member of the SDL_RWops structure.
*

SDL_RWread reads up to maxnum objects each of size size from the data source to the area pointed at by ptr. green

green


CategoryAPI, CategoryIO

(Page Info.)
Feedback
Please include your contact information if you'd like to receive a reply.
Submit