I have seen uses of
@ in front of certain functions, like the following:
$fileHandle = @fopen($fileName, $writeAttributes);
What is the use of this symbol?
It suppresses errors.
See Error Control Operators in the manual:
PHP supports one error control operator: the at sign (@). When prepended to an expression in PHP, any error messages that might be generated by that expression will be ignored.
If you have set a custom error handler function with set_error_handler() then it will still get called, but this custom error handler can (and should) call error_reporting() which will return 0 when the call that triggered the error was preceded by an @...