I've seen some horrific code written in Perl, but I can't make head nor tail of this one:
select((select(s),$|=1)[0])
It's in some networking code that we use to communicate with a server and I assume it's something to do with buffering (since it sets $|).
But I can't figure out why there's multiple select calls or the array reference. Can anyone help me out?
select($fh)
Select a new default file handle. See http://perldoc.perl.org/functions/select.html
(select($fh), $|=1)
Turn on autoflush. See http://perldoc.perl.org/perlvar.html
(select($fh), $|=1)[0]
Return the first value of this tuple.
select((select($fh), $|=1)[0])
select it, i.e. restore the old default file handle.
Equivalent to
$oldfh = select($fh);
$| = 1;
select($oldfh);
which means
use IO::Handle;
$fh->autoflush(1);
as demonstrated in the perldoc page.