#include <errno.h>
#include <stdio.h>
#include <unistd.h>

int
rpl_fflush(FILE *fp)
{
#if defined(__DragonFly__)
	struct __FILE_public *fp_ = (struct __FILE_public *)fp;
#else
#define	fp_ fp
#endif
	off_t pos;

	/* NULL pointer or writeable stream: use normal fflush. */
	if (fp == NULL || (fp_->_flags & (__SWR | __SRW)) != 0)
		return fflush(fp);

	/* Get current position, possibly different from file pointer. */
	pos = ftello(fp);
	if (pos == -1) {
		errno = EBADF;
		return -1;
	}
	/* Purge buffers. */
	if (fpurge(fp) == EOF)
		return -1;

	/*
	 * Disable seek optimisation.  This is forces the following
	 * fseeko to seek the actual position and not realign
	 * the file pointer on a block boundary.
	 */
	fp_->_flags |= __SNPT;

	return fseeko(fp, pos, SEEK_SET);
}