note 91646 added to function.mime-content-type

I see a lot of comments suggesting doing file extension sniffing (i.e. assuming .jpg files are JPEG images) when proper file-type sniffing functions are unavailable. I want to point out that there is a much more accurate way. If neither mime_content_type() nor Fileinfo is available to you and you are running *any* UNIX variant since the 70s, including Mac OS, OS X, Linux, etc. (and most web hosting is), just make a system call to 'file(1)'. Doing something like this: <?php echo system("file -bi '<file path>'"); ?> will output something like "text/html; charset=us-ascii". Some systems won't add the charset bit, but strip it off just in case. The '-bi' bit is important. However, you can use a command like this: <?php echo system("file -b '<file path>'"); // without the 'i' after '-b' ?> to output a human-readable string, like "HTML document text", which can sometimes be useful. The only drawback is that your scripts will not work on Windows, but is this such a problem? Just about all web hosts use a UNIX. It is a far better way than just examining the file extension. ---- Server IP: 117.104.162.229 Probable Submitter: 58.96.44.86 (proxied: 58.96.44.86) ---- Manual Page -- http://www.php.net/manual/en/function.mime-content-type.php Edit -- https://master.php.net/note/edit/91646 Del: integrated -- https://master.php.net/note/delete/91646/integrated Del: useless -- https://master.php.net/note/delete/91646/useless Del: bad code -- https://master.php.net/note/delete/91646/bad+code Del: spam -- https://master.php.net/note/delete/91646/spam Del: non-english -- https://master.php.net/note/delete/91646/non-english Del: in docs -- https://master.php.net/note/delete/91646/in+docs Del: other reasons-- https://master.php.net/note/delete/91646 Reject -- https://master.php.net/note/reject/91646 Search -- https://master.php.net/manage/user-notes.php