DRAFT |
SDL_RWseek
Use this function to seek within an SDL_RWops data source.
Syntax
long SDL_RWseek(SDL_RWops* context,
long offset,
int whence)
Function Parameters
context |
a pointer to an SDL_RWops structure |
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 source.
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.
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 |
