I hate that google can not search for symbols. I saw this in some sample code and wondered why there is an @ sign before the readfile function:
@readfile($filename);
What does it mean different to without an @ symbol?
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1Also, as a heads up for next time whenever you come across a symbol, try spelling it out instead, i.e 'at sign' you might be able to find more results. – Anthony Forloney Apr 16 '10 at 16:30
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3Also, PHP has a pretty good online help. For the most part you can simply do `http://php.net/[something]` and get to the right page. And yes, in this case, the `[something]` can actually be `@`: http://php.net/@ – Joey Apr 16 '10 at 16:33
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use this while googling "@readfile()" – RSK Apr 16 '10 at 19:12
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would you consider renaming the issue to something like "what does the @ symbol mean before a PHP function?" – tmsimont Jul 08 '11 at 17:35
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An @ before a command in PHP means that no errors are printed. It's called the error control operator.
If you removed the @ and readfile would encounter an error (such as not being able to read the file), then—depending on your PHP settings—the error message will be amidst your site content; something you rarely, if ever, want. (It gets worse even, if this happens before a call to header() or start_session() because once content is sent, the headers can't be written anymore.)
Joey
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It is PHP's error suppression operator. With it you can suppress error messages.
Tip:
Simply don’t use the error suppression operator with speed-critical code.
Future:
Because @ operator is very slow, it won't work on ini_set eg @ini_set in future version of PHP eg PHP6
Important Reading:
Sarfraz
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