PerlIO::code - Calls a subroutine with I/O interface

This document describes PerlIO::code version 0.03

	use PerlIO::code; # need to say explicitly

	# make an input filter
	open my $in, '<', sub{ uc scalar <> };
	print while <$in>;

	# make an output filter
	open my $out, '>', sub{ print uc shift };
	print $out while <>;

	# it accepts an extra argument
	sub my_readline{
		my($fh) = @_;
		my $line = <$fh>;
		# ...filterling...
		return $line;
	}
	open my $fh, '<', \&my_readline, \*STDIN;

PerlIO::code helps to make an simple I/O filter. It is easier than tie, but provides very limited functions. All it can do is to do readline() and print().

• For some reason, the actual layer name of PerlIO::code is :Code, not :code.
• PerlIO::code is slower than the tie interface.
• open my $in, '<', sub{ "foo" }; my $s = <$in>; makes an endless loop, because the internal readline routine reads $in on until reaching EOF, which is never reached.

No configuration files or environment variables.

Perl 5.8.1 or later, and a C compiler.

No bugs have been reported.

Please report any bugs or feature requests to bug-perlio-code@rt.cpan.org, or through the web interface at http://rt.cpan.org/.

PerlIO::Util.

Tie::Handle.

PerlIO::via.

PerlIO.

Goro Fuji <gfuji(at)cpan.org>.

Copyright (c) 2008, Goro Fuji <gfuji(at)cpan.org>. Some rights reserved.

This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See perlartistic.