使用stream_filter_ *在PHP中处理大型（超过1 Gig）文件

$fp_src=fopen('file','r');

$filter = stream_filter_prepend($fp_src, 'convert.iconv.ISO-8859-1/UTF-8');

while(fread($fp_src,4096)){
    ++$count;
    if($count%1000==0) print ftell($fp_src)."\n";
} 
$fp_src=fopen('file','r');

$filter = stream_fi