The $_[0] is the socket that is passed from the accept into the sub. The filename is looked up and if it is executable, a pipe is created with it, otherwise it is opened directly. In either case the contents of the resulting IO::All object are fed into the $_[0] socket. Very similar to the simplistic use of '<' in:

$contents < io 'file.txt';

[download]

So this oneline web server can send the contents of simple files, or the generated output from executables.

Update: The reason you couldn't find anything in perldoc is because this is an operator that has been overridden to act in this way by IO::All which is where the simple example above comes from. Thus, you can only use the '<' operator this way with IO:All objects.

In reply to Re: direct data to a socket by Loops
in thread direct data to a socket by demoralizer

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