header_put_byte (SF_PRIVATE *psf, char x)
{	if (psf->headindex < SIGNED_SIZEOF (psf->header) - 1)
		psf->header [psf->headindex++] = x ;
} /* header_put_byte */
The software performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer.