Description:
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a php script doing file opretaions might benefit from posix_fadvice, could that be added? 

additional note: it might be worth looking into adding posix_fadvice calls to file_put_contents / file_get_contents , namely POSIX_FADV_SEQUENTIAL,  because those always are.

Test script:
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<?php
$fp=fopen('bigfile','rb');
// tell the kernel that i'm probably only going to access this data once,
// so it's probably a waste to add this to the filesystem cache
posix_fadvice($fp,0,0,POSIX_FADV_NOREUSE); 

// tell the kernel that i'm probably going to read from byte 12345 to 123456789 sequentially, so optimize for that
posix_fadvice($fp,12345,123456789,POSIX_FADV_SEQUENTIAL); 
fseek($fp,12345);
$content=fread($fp,123456789-12345);
fclose($content);

// aka file_get_contents('bigfile',false,NULL,12345,123456789-12345);