Sadly, this wrong example is present even in the PHP manual. The author must have been really frustrated and added three Content-Type headers. What would it be like to not having to worry about old versions of Internet Explorer? Note: the quotes in the filename are required in case the file may contain spaces. The code above will fail in IE6 unless the following are added:. Now, the use of Cache-Control is wrong in this case, especially to both values set to zero, according to Microsoft , but it works in IE6 and IE7 and later ignores it so no harm done.
If you still get strange results when downloading especially in IE , make sure that the PHP output compression is disabled, as well as any server compression sometimes the server inadvertently applies compression on the output produced by the PHP script. Historically it had some performance issues and while the documentation claims there are no memory problems, real-life scenarios beg to differ — output buffering and other subtle things.
Regardless, if you need byte ranges support, you still have to output the old-fashioned way. You just output a header and the module takes care of the rest. This is the source of many seemingly obscure errors. If you have output buffering, the file will not be sent to the user in chunks but only at the end of the script.
At the start of your script, after checking the file if it exists, etc. Be aware that multiple ranges can be specified e. If the range is not valid, you must output. Do not try to guess or fix the range s as it may result in corrupted downloads, which are more dangerous than failed ones. Many developers forget to send the code or the Accept-Ranges. Yet others forget that when you send a range, the Content-Length must match the length of the range rather than the size of the whole file.
All users are strongly encouraged to upgrade their environments to newest PHP version. Please read our guides for Migrating from PHP 5. You can download a copy in the documentation archives. You can also find the PHP 5 legacy manual on the Zend site, which was created from the official archives. Although from 5. If you use any of the above code for downloadinng files, Internet Explorer will change the filename if it has multiple periods in it to something with square brackets.
The following function retrieves a line in a file, regardless of its size, so you won't get an error if the file's size is beyond php's allowed memory limit the string has to be below however , which is something i was needing for accessing a big log file generated by a webhost. If the file is small, it would be better to use "file " however. Tom, the idea for the examples below is to ensure the user has proper credentials before serving the file. With that security in mind, the suggestion of a redirection seems like a risky idea.
Anyone with a modicum of networking experience can run a TCP trace and see the Redirect response, as it is actually a response received by the client browser; the browser then makes a subsequent http request for the URL provided in the Location header. When that response is captured by wireshark, the 'secret' location is then exposed and can be shared with anyone who wishes to bypass the authorization routines in the php.
The only way to secure this would be for the Redirection response to include some kind of unique, per-request, expiring authorization token, either on the end of the url or in a set-cookie, that is then checked by an authorization module implemented within the hosting webserver. Otherwise, you're relegated to the methods described below. Somehow all code samples for downloads, described here, doesn't work right for me. When I download a big file readfile or fread in b mode, the final file hasn't the same md5 like the originial.
Birmingham, Al " ;? Various scripts suggested here attempt to deliver a file for download to a client. An alternative is to let the web server can handle http by redirecting to the file in question. It's not uncommon e. The server's mime type configuration will determine client behavior. For apache, if defaults in mime. If really necessary, these could even by written by the PHP script before it redirects. I spent a while trying to get this to work so I thought I'd share.
Here's how to read a remote binary file using fread. I used that number because it seemed safe, but you can increment it all you want I guess.
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