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Revision 13 as of 2011-01-12 00:13:16
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Comment: update content - RWops stream
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Use this function to seek within an SDL_RWops data source. Use this function to seek within an SDL_RWops data stream.
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||'''context'''||an SDL_RWops structure ^containing the seek function???^|| ||'''context'''||^a data stream containing the seek function???^||
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Returns the final offset in the data source after the seek. Returns the final offset in the data stream after the seek.

SDL_RWseek

Use this function to seek within an SDL_RWops data stream.

Syntax

long SDL_RWseek(SDL_RWops* context,
                long       offset, 
                int        whence)

green

Function Parameters

context

a data stream containing the seek function???

offset

an offset in bytes, relative to whence location; can be negative

whence

any of RW_SEEK_SET, RW_SEEK_CUR, RW_SEEK_END; see Remarks for details

Return Value

Returns the final offset in the data stream after the seek.

Code Examples

*

#include <stdio.h>
#include "SDL_rwops.h"

int main()
{
  long length;
  SDL_RWops *rw=SDL_RWFromFile("myfile.bin","rb");
  if(rw==NULL)
  {
    fprintf(stderr,"Couldn't open myfile.bin\n");
    return(1);
  }

  /* Seek to 0 bytes from the end of the file -- i.e. the exact end of file */
  length=SDL_RWseek(rw,0,SEEK_END);
  SDL_RWclose(rw);
  if(length<0)
  {
    fprintf(stderr,"Could not seek inside myfile.bin\n");
    return(2);
  }

  fprintf(stderr,"myfile.bin is %d bytes long\n",length);
  return(0);
}


*

Remarks

*
This is not a predefined function, just a macro that calls whatever seek function has been placed in the SDL_RWops structure.
*

SDL_RWseek seeks to offset relative to whence. green

whence may be any of the following values:

RW_SEEK_SET

seek from the beginning of data

RW_SEEK_CUR

seek relative to current read point

RW_SEEK_END

seek relative to the end of data


CategoryAPI, CategoryIO

None: SDL_RWseek (last edited 2015-06-20 20:01:11 by PhilippWiesemann)

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