In fact, that uses a perlio layer silently.

I've been wishing a perlio layer that allows you to simply open a stream that behaives like any tied handle eg.

use StringBuffer;
use PerlIO::Tied;
# Note: never close one of the three standard handles. It's almost alw
+ays a bad idea.
open OLDSTDOUT, ">&=STDOUT";
open STDOUT, ">:tied(StringBuffer)"; # I presume extra arguments to ti
+e get passed as extra argument to open
print STDOUT "this magically gets put to \$stdout\n";
open STDOUT, ">&=OLDSTDOUT";
print STDOUT "this gets put to the original standard output again\n";
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This gets even more useful if you want to use a tied io handle from the command line eg. perl -MPerlIO::Tied -we 'some code' ':tied(SomeModule, arguments)'.