The @ is used to dereference an array reference: perldoc perlreftut.

From perldoc IO::Select (for the select method):

The result will be an array of 3 elements, each a reference to an array which will hold the handles that are ready for reading, writing and have exceptions respectively.

See also: Writeup Formatting Tips

In reply to Re: @$ variable type by toolic
in thread @$ variable type by Anonymous Monk

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