> 2) If the sparse flag is set, then ext2_file_read() will stop the read > when it runs into the first uninitialized or sparse block. That is, > consider the example file which has 8k of data, a 4k uninitialized > block, and then 12k of data after that. If the sparse flag is passed > to ext2_file_open(), then ext2fs_file_read(fd, buf, 16384, &got) will > read 8k of data into buf, and return with got set to 8192. > > 3) To distinguish between EOF and a sparse block, if the current file > offset is pointed at a sparse/uninitialized block, and the sparse flag > was passed to ext2_file_open(), then in addition to *got getting set > 0, ext2_file_read() will also return a new error code, > EXT2_ET_READ_HOLE_FOUND. Given that the current model of ext2fs_file_read is that it returns some valid data in *got, AND the reason it stopped short as the retval, wouldn't it make more sense to return EXT2_ET_READ_HOLE_FOUND from the *first* read call? It's a minor thing, as you just end up falling back to the Unix syscall model of deferring the error until the next read call, but wouldn't it be more consistent? -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
