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Differences between revisions 20 and 21
Revision 20 as of 2014-09-23 19:51:55
Size: 1728
Comment: Fixed constant name in example (Feedback 2014-09-23) so no C standard include needed.
Revision 21 as of 2015-04-10 23:35:19
Size: 1817
Comment: Added more related functions.
Deletions are marked like this. Additions are marked like this.
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 .[[SDL_RWtell]]
 .[[SDL_RWread]]
 .[[SDL_RWwrite]]
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 .[[SDL_RWread]]
 .[[SDL_RWtell]]
 .[[SDL_RWwrite]]
 .[[SDL_RWFromFile]]
 .[[SDL_RWFromFP]]
 .[[SDL_RWFromMem]]
 .[[SDL_RWFromConstMem]]

SDL_RWseek

Use this function to seek within an SDL_RWops data stream.

Syntax

Sint64 SDL_RWseek(SDL_RWops* context,
                  Sint64     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 stream after the seek or -1 on error.

Code Examples

SDL_RWops *rw = SDL_RWFromFile("myfile.bin", "rb");
if (rw != NULL) {
    /* Seek to 0 bytes from the end of the file */
    Sint64 length = SDL_RWseek(rw, 0, RW_SEEK_END);
    SDL_RWclose(rw);
    if (length < 0) {
        printf("Could not seek inside myfile.bin\n");
    } else {
        printf("myfile.bin is %d bytes long\n", length);
    }
}

Remarks

This function seeks to offset relative to whence

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

If this stream can not seek, it will return -1.

SDL_RWseek is actually a macro that calls the SDL_RWops's seek method appropriately, to simplify application development.


CategoryAPI, CategoryIO

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

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