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Top Forums Programming Newbie question on exec,fork, wait,pipe C Post 302528091 by Neo on Monday 6th of June 2011 11:40:47 AM
Old 06-06-2011
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IO::Pipe(3pm)						 Perl Programmers Reference Guide					     IO::Pipe(3pm)

NAME
IO::Pipe - supply object methods for pipes SYNOPSIS
use IO::Pipe; $pipe = new IO::Pipe; if($pid = fork()) { # Parent $pipe->reader(); while(<$pipe>) { ... } } elsif(defined $pid) { # Child $pipe->writer(); print $pipe ... } or $pipe = new IO::Pipe; $pipe->reader(qw(ls -l)); while(<$pipe>) { ... } DESCRIPTION
"IO::Pipe" provides an interface to creating pipes between processes. CONSTRUCTOR
new ( [READER, WRITER] ) Creates an "IO::Pipe", which is a reference to a newly created symbol (see the "Symbol" package). "IO::Pipe::new" optionally takes two arguments, which should be objects blessed into "IO::Handle", or a subclass thereof. These two objects will be used for the system call to "pipe". If no arguments are given then method "handles" is called on the new "IO::Pipe" object. These two handles are held in the array part of the GLOB until either "reader" or "writer" is called. METHODS
reader ([ARGS]) The object is re-blessed into a sub-class of "IO::Handle", and becomes a handle at the reading end of the pipe. If "ARGS" are given then "fork" is called and "ARGS" are passed to exec. writer ([ARGS]) The object is re-blessed into a sub-class of "IO::Handle", and becomes a handle at the writing end of the pipe. If "ARGS" are given then "fork" is called and "ARGS" are passed to exec. handles () This method is called during construction by "IO::Pipe::new" on the newly created "IO::Pipe" object. It returns an array of two objects blessed into "IO::Pipe::End", or a subclass thereof. SEE ALSO
IO::Handle AUTHOR
Graham Barr. Currently maintained by the Perl Porters. Please report all bugs to <perl5-porters@perl.org>. COPYRIGHT
Copyright (c) 1996-8 Graham Barr <gbarr@pobox.com>. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. perl v5.12.1 2010-04-26 IO::Pipe(3pm)
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